Using your Head is Permitted

Links to past riddles and solutions are from this page. If you know any good riddles that you think might fit in, you're welcome to send them to the puzzlemaster at riddles brand.scso.com . The puzzlemaster is Michael Brand.

128. October 2017 Riddle Solution Coda 127. September 2017 Riddle Solution Real Sorting 126. August 2017 Riddle Solution Open Day Riddle 125. July 2017 Riddle Solution Two Classics 124. June 2017 Riddle Solution Real Random Walk 123. May 2017 Riddle Solution More One-to-one Functions 122. April 2017 Riddle Solution Soko-2048-ban 121. March 2017 Riddle Solution Ten Years of UyHiP 120. February 2017 Riddle Solution Sublinear Primes 119. January 2017 Riddle Solution Linear Primes 118. December 2016 Riddle Solution Return to Prepostria 117. November 2016 Riddle Solution Leibniz 300 116. October 2016 Riddle Solution Concave Quadrilaterals 115. September 2016 Riddle Solution Random Errors 114. August 2016 Riddle Solution Mutual Acquaintances 113. July 2016 Riddle Solution Tower of Hats 112. June 2016 Riddle Solution Three Stone Paths 111. May 2016 Riddle Solution Means 110. April 2016 Riddle Solution Which Number? 109. March 2016 Riddle Solution MFCIS Margin 108. February 2016 Riddle Solution Planes on a Hypercube 107. January 2016 Riddle Solution Latin 106. December 2015 Riddle Solution Common Subgraphs 105. November 2015 Riddle Solution Unbiased Estimation 104. October 2015 Riddle Solution Universal Probabilities 103. September 2015 Riddle Solution Coins on a Board 102. August 2015 Riddle Solution 3xn+1 101. July 2015 Riddle Solution Centenary 100. June 2015 Riddle Solution Odds and Evens 99. May 2015 Riddle Solution Expanding Sets 98. April 2015 Riddle Solution Even More Quadrilateral Inequalities 97. March 2015 Riddle Solution More Quadrilateral Inequalities 96. February 2015 Riddle Solution Quadrilateral Inequality 95. January 2015 Riddle Solution Surjection/Injection 94. December 2014 Riddle Solution Casinos 93. November 2014 Riddle Solution One Coin 92. October 2014 Riddle Solution Two Coins 91. September 2014 Riddle Solution Even More Jigsaw Puzzles 90. August 2014 Riddle Solution Balancing Rounded Irrationals 89. July 2014 Riddle Solution More Jigsaw Puzzles 88. June 2014 Riddle Solution The Missing Piece 87. May 2014 Riddle Solution Fun with Random Bits 86. April 2014 Riddle Solution 2048 85. March 2014 Riddle Solution Squares and Rectangles 84. February 2014 Riddle Solution On the Shoulders of Giants 83. January 2014 Riddle Solution Table-turning Genie 82. December 2013 Riddle Solution Christmas at MegaCorp 81. November 2013 Riddle Solution Parenthesis Values 80. October 2013 Riddle Solution King Tours 79. September 2013 Riddle Solution Rook Tours 78. August 2013 Riddle Solution Fun with L2 77. July 2013 Riddle Solution PSP 76. June 2013 Riddle Solution Horner's Dilemma 75. May 2013 Riddle Solution Coin Verification 74. April 2013 Riddle Solution k-resistance 73. March 2013 Riddle Solution A185028 72. February 2013 Riddle Solution More Takeaways 71. January 2013 Riddle Solution Take Away 70. December 2012 Riddle Solution A Problem with Neighbors 69. November 2012 Riddle Solution Fun with Normal Distributions 68. October 2012 Riddle Solution Rectangling Another Rectangle 67. September 2012 Riddle Solution Hydra Games 66. August 2012 Riddle Solution Euler Numbers 65. July 2012 Riddle Solution Stepping Contest 64. June 2012 Riddle Solution Lucky Numbers 63. May 2012 Riddle Solution Two Polygons 62. April 2012 Riddle Solution Natural Partitions 61. March 2012 Riddle Solution Rectangling the Rectangle 60. February 2012 Riddle Solution Space-efficient Exponentiation 59. January 2012 Riddle Solution From A to B 58. December 2011 Riddle Solution Post-office Tetrahedra 57. November 2011 Riddle Solution Post-office Volumes 56. October 2011 Riddle Solution Post-office Dilemma 55. September 2011 Riddle Solution Gladiators 54. August 2011 Riddle Solution Equinox Counting 53. July 2011 Riddle Solution Bananas 52. June 2011 Riddle Solution Improved FFT 51. May 2011 Riddle Solution Fun with Trigonometry 50. April 2011 Riddle Solution Cyclone Frogs 49. March 2011 Riddle Solution Lights-Out 48. February 2011 Riddle Solution Tea or Coffee 47. January 2011 Riddle Solution Prepostria 46. December 2010 Riddle Solution 2-bend Graph Embeddings 45. November 2010 Riddle Solution DNFs and Symmetric Functions 44. October 2010 Riddle Solution Abraham and Benjamin 43. September 2010 Riddle Solution Gloved Prisoners 42. August 2010 Riddle Solution Tetrahedron Crossing 41. July 2010 Riddle Solution A Tribute to Gardner 40. June 2010 Riddle Solution Cyclic Permutations 39. May 2010 Riddle Solution Segment-preserving Mappings 38. April 2010 Riddle Solution Self Assembled Numbers 37. March 2010 Riddle Solution Taylor Series 36. February 2010 Riddle Solution Laura Sort 35. January 2010 Riddle Solution Encyclopedia Sort 34. December 2009 Riddle Solution Dividing the Naturals 33. November 2009 Riddle Solution Polynomial Solutions 32. October 2009 Riddle Solution Local Minima 31. September 2009 Riddle Solution Pythagorean Triplets 30. August 2009 Riddle Solution Boolean Functions 29. July 2009 Riddle Solution Steiner Systems with k=3 28. June 2009 Riddle Solution Counting Solutions to x2+y2 27. May 2009 Riddle Solution Perfect Numbers 26. April 2009 Riddle Solution Counting Triangles 25. March 2009 Riddle Solution Fun with Uniform Distributions 24. February 2009 Riddle Solution O(1) Factorial 23. January 2009 Riddle Solution O(1) Sorting 22. December 2008 Riddle Solution O(n) Sorting 21. November 2008 Riddle Solution Combinations of 1s 20. October 2008 Riddle Solution 19. September 2008 Riddle Solution Permutation Reversal 18. August 2008 Riddle Solution Trisecting the Square 17. July 2008 Riddle Solution Sudoku 16. June 2008 Riddle Solution Knights of the Round Table 15. May 2008 Riddle Solution Permutation Partial Sums 14. April 2008 Riddle Solution Partial Harmonic Series 13. March 2008 Riddle Solution Lexicographic Sorting 12. February 2008 Riddle Solution Board Game Strategies 11. January 2008 Riddle Solution QCPL 10. December 2007 Riddle Solution One-to-one Functions 9. November 2007 Riddle Solution License Plate Numbers 8. October 2007 Riddle Solution Jigsaw Puzzles 7. September 2007 Riddle Solution Clique Partitioning 6. August 2007 Riddle Solution Three Points through every Line 5. July 2007 Riddle Solution Digit Anagrams 4. June 2007 Riddle Solution Mesh Animals 3. May 2007 Riddle Solution Chico and Dico 2. April 2007 Riddle Solution 3025 1. March 2007 Riddle Solution Primitive Polynomials

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