Ponder this

Welcome to our monthly puzzles

You are cordially invited to match wits with some of the best minds in IBM Research.

Seems some of us can't see a problem without wanting to take a crack at solving it. Does that sound like you? Good. Forge ahead and ponder this month's problem. We'll post a new one every month, and allow a month for you to submit solutions (we may even publish submitted answers, especially if they're correct). We usually won't reply individually to submitted solutions but every few days we will update a list of people who answered correctly. At the beginning of the next month, we'll post the answer.

• Here is the solution for our May 2013 problem.
• And now... here's our June challenge!

So give your mind a break from its routine---you never know what other problems you may solve in the process!

The current puzzlemaster is Oded Margalit. He took over from James B. Shearer, who took over from the original puzzlemaster Don Coppersmith, in October 2005.

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If you have any problems you think we might enjoy, please send them in. All replies should be sent to: webmster@us.ibm.com

Archive

1. June 2013

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2. May 2013

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3. April 2013

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4. March 2013

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5. February 2013

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6. January 2013

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7. December 2012

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8. November 2012

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9. October 2012

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10. September 2012

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11. August 2012

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12. July 2012

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13. June 2012

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14. May 2012

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15. April 2012

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16. March 2012

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17. February 2012

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18. January 2012

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19. December 2011

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20. November 2011

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21. October 2011

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22. September 2011

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23. August 2011

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24. July 2011

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25. June 2011

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26. May 2011

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27. April 2011

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28. March 2011

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29. February 2011

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30. January 2011

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31. December 2010

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32. November 2010

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33. October 2010

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34. September 2010

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35. August 2010

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36. July 2010

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37. June 2010

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38. May 2010

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39. April 2010

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40. March 2010

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41. February 2010

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42. January 2010

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43. December 2009

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44. November 2009

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45. October 2009

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46. September 2009

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47. August 2009

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48. July 2009

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49. June 2009

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50. May 2009

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51. April 2009

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52. March 2009

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53. February 2009

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54. January 2009

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55. December 2008

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56. November 2008

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57. October 2008

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58. September 2008

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59. August 2008

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60. July 2008

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61. June 2008

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62. May 2008

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63. April 2008

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64. March 2008

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65. February 2008

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66. January 2008

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67. December 2007

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68. November 2007

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69. October 2007

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70. September 2007

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71. August 2007

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72. July 2007

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73. June 2007

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74. May 2007

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75. April 2007

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76. March 2007

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77. February 2007

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78. January 2007

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79. December 2006

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80. November 2006

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81. October 2006

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82. September 2006

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83. August 2006

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84. July 2006

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85. June 2006

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86. May 2006

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87. April 2006

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88. March 2006

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89. February 2006

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90. January 2006

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91. December 2005

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92. November 2005

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93. October 2005

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94. September 2005

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95. August 2005

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96. July 2005

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97. June 2005

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98. May 2005

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99. April 2005

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100. March 2005

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101. February 2005

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102. January 2005

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103. December 2004

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104. November 2004

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105. October 2004

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106. September 2004

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107. August 2004

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108. July 2004

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109. June 2004

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110. May 2004

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111. April 2004

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112. March 2004

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113. February 2004

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114. January 2004

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115. November 2003

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116. December 2003

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117. October 2003

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118. September 2003

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119. August 2003

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120. July 2003

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121. June 2003

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122. May 2003

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123. April 2003

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124. March 2003

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125. February 2003

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126. January 2003

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127. December 2002

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128. November 2002

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129. October 2002

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130. September 2002

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131. August 2002

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132. July 2002

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133. June 2002

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134. May 2002

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135. April 2002

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136. March 2002

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137. February 2002

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138. January 2002

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139. December 2001

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140. November 2001

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141. October 2001

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142. September 2001

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143. August 2001

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144. July 2001

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145. June 2001

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146. May 2001

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147. April 2001

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148. March 2001

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149. February 2001

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150. January 2001

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151. December 2000

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152. November 2000

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153. October 2000

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154. September 2000

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155. August 2000

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156. July 2000

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157. June 2000

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158. May 2000

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159. April 2000

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160. March 2000

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161. February 2000

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162. January 2000

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163. December 1999

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164. November 1999

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165. October 1999

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166. September 1999

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167. August 1999

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168. July 1999

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169. June 1999

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170. May 1999

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171. April 1999

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172. March 1999

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173. February 1999

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174. January 1999

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175. December 1998

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176. November 1998

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177. October 1998

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178. September 1998

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179. August 1998

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180. July 1998

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181. June 1998

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182. May 1998

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