Maths puzzles from Computer Weekly's regular maths puzzle column.

Think you're a mathematical genius? Take on the Puzzler!

14 July 2009: Flesh out the skeleton with the number seven

7 July 2009: Plus ca change, plus c’est la meme alphametic

30 June 2009: Place the values to unlock the secret of the pyramid

23 June 2009: 34 holds the key to the magic square

16 June 2009: Never the twain sums' digits' values shall meet

9 June 2009: Conundrums pay tribute to a singular digit – number 7

2 June 2009: Leave the calculator alone to deduce the missing digit

26 April 2009: Join all the dots without lifting pen from paper

19 April 2009: Score a century with an improper fraction

12 April 2009: Put digits on the heptagon and keep all sides constant

5 April 2009: Find the value of the letters to solve the double sum

28 April 2009: Reconfigure the digits to find another progression

21 April 2009: Find out how the hidden alphametic sum adds up

14 April 2009: Separate the triplet digits by their numerical value

31 March 2009: Deduce the location of the remaining domino tiles

24 March 2009: Break the product down into factors summing to 100

17 March 2009: Fashion a square to house all nine prime numbers

10 March 2009: Number 4 leads the way in decyphering cryptarithm

24 February 2009: Square consecutive primes to sum line-total primes

17 February 2009: In search of the Holy Grail of magic squares

10 February 2009: Complete the Latin square without repitition

27 January 2009: Use all digits 1 to 9 to make six primes summing 207

13 January 2009: Get through a couple of beers to get drunk

16 December 2008: A mind reading trick to amaze at your Xmas party

9 December 2008: Solve the alphametic to help a penniless student

2 December 2008: Extrapolate the values to flesh out the long division

25 November: Take away the values to add the trilateral digits

18 November: Make a constant of 21 to hex the conundrum

4 November: Find the colour-values to deduce the third row

28 October: Unswop the pairs of numbers to bring back the magic

21 October: Find the permutable prime and two spoiling factors

7 October: Turn the numbers inside out to make a magic square

30 September 2008: Find out the side lengths of a Pythagorean triangle

23 September 2008: Square the alphametic pie to reveal the correct digits

16 September 2008: Change the digits around to deduce the correct sum

9 September 2008: Keep the digits different to solve the equation

2 September 2008: Use all the numbers to reconstruct the sum

26 August 2008: Go around in circles to complete a square wheel

12 August 2008: Unlock the secrets of the numerical pyramid

5 August 2008: Rewrite the equation to find the missing numbers

29 July 2008: Read the writing on the wall to solve the sum

22 July 2008: Lay out the pentacle numbers to find the constant

15 July 2008: Get up to date with the missing numbers

8 July 2008: Add or take one to make the sum work

1 July 2008: Keep a poker face with a dealing conundrum

24 June 2008: Place the squares to form a 13x13 figure

17 June 2008: Doubly truncatable primes

6 May 2008: Six in the bed and the little one said...

29 April 2008: Triangles - can you make 11 from seven?

22 April 2008: A game of avoiding the neighbours

15 April 2008: Go round in circles to find the constant

8 April 2008: Place seven discs so they are inequidistant

1 April 2008: Find squares made of two-digit primes

Post all Puzzler enquiries and contributions to: Jim Howson, 5 Hilltop Gardens, Dartford, Kent DA1 5JF