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Prize crossnumber, Issue 14

Our original prize crossnumber is featured on pages 60 and 61 of Issue 14.

Rules

  • The down clues are provided as normal. The across clues are provided in alphabetical order without their clue numbers or lengths.
  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. Solvers may wish to use the OEIS, Wikipedia, Python, a book of log tables, etc to (for example) obtain a list of cube numbers, but no programming should be necessary to solve the puzzle. As usual, no numbers begin with 0.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, submit the sum of the across entries using this form by 14 March 2022. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 1 May 2022.

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Crossnumber winners, issue 13

Hello everyone! It’s time to announce the winners of the issue 13 crossnumber competition! Before we reveal the winners, here is the solution of the crossnumber.

1 6 9 9 9 9 9 9 9
8 5 1 1 1 1 1 1 6 4
3 2 0 9
6 3 3 5 2 1 0 1 6 4
9 0 0 9 6 0 7 1 4
4 0 2 9 3 1 1 9 6 3
0 9 7 1
1 5 7 9 2 9 9 9 7 3
2 2 2 9 9 9 9 0 0
1 7 9 2 7 9 4 9 1 2
3 2 0 2
6 4 7 2 9 1 0 2 8 5
1 0 0 3 4 3 1 6 9

The sum of the across clues was 13704.

There were 82 entries, 68 of which were correct. The randomly selected winners are:

  1. Alistair Benford, who wins a £100 Maths Gear goody bag,
  2. Miguel Ángel Morales Medina, who wins a Chalkdust T-shirt,
  3. Yuliya Nesterova, who wins a Chalkdust T-shirt,
  4. Martin Schuh, who wins a Chalkdust T-shirt.

Well done to Alistair, Miguel, Yuliya and Martin, and thanks to everyone else who attempted the crossnumber. Keep your eyes peeled for issue 14’s puzzle, which will be released very soon…

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Crossnumber winners, issue 12

Hello everyone! As the 13th Chalkdust prize crossnumber has just been released, it’s time to announce the winners of the issue 12 crossnumber competition! Before we reveal the winners, here is the solution of the crossnumber.

6 7 2 9 9 9 7 4 1 3 2 4
4 2 2 1 9 9 9 8 0 1 5
2 1 4 1 4 9 1 1 3 7 6 2
8 4 1 2
1 5 1 4 4 7 3 3 3 9 4 5
5 4 4 4 2 4 3 3 3 9 4
1 4 8 7 3 8 3 3 3 3 3 9
4 3 9 2
1 4 1 4 1 1 2 6 4 1 0 1
4 7 9 2 1 1 9 2 2 2 0
4 4 1 9 6 1 7 5 9 1 2 4
3 9 5 4
7 2 3 3 3 3 1 5 1 3 6 3
5 1 1 3 3 1 5 6 9 3 0
7 3 5 3 3 3 4 9 5 3 6 0

The sum of the across clues was 19404.

There were 63 entries, 52 of which were correct. The randomly selected winners are:

  1. Robert Kerry, who wins a £100 Maths Gear goody bag,
  2. Nick Keith, who wins a Chalkdust T-shirt,
  3. Sarah Gross, who wins a Chalkdust T-shirt,
  4. Pamela Docherty, who wins a Chalkdust T-shirt.

Well done to Robert, Nick, Sarah, and Pamela, and thanks to everyone else who attempted the crossnumber. Hope you enjoy issue 13’s puzzle

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Prize crossnumber, Issue 13

Our original prize crossnumber is featured on pages 58 and 59 of Issue 13.

Rules

  • Each clue in this crossnumber contains two statements joined by a logical connective. If the connective is AND, then both the statements are true. If the connective is NAND, then at most one of the statements is true. If the connective is OR, then at least one of the statements is true. If the connective is NOR, then neither of the statements is true. If the connective is XOR, then exactly one of the statements is true. If the connective is XNOR, then either the statements are both true or they are both false.
  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, enter the sum of the across entries below by 18 September 2021. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 1 November 2021.

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Prize crossnumber, Issue 12

Our original prize crossnumber is featured on pages 56 and 57 of Issue 12.

Rules

  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, enter the sum of the across clues below by 14 March 2021. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 1 May 2021.

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Prize crossnumber, Issue 11

Our original prize crossnumber is featured on pages 56 and 57 of Issue 11.

Rules

  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, enter the sum of the across clues below by 3 September 2020. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 1 October 2020.

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Crossnumber winners, issue 10

Hello everyone! It’s time to announce the winners of the Chalkdust prize crossnumber #10! Before we reveal the winners, here is the solution of the crossnumber.

1 0 8 9 0 2 2 2 2 2 2 2 2 2
1 9 5 2 8 6 7 5
1 0 8 9 5 2 5 8 6
1 9 7 5 4 3 2 0 4 1 2
0 0 5 4 1 1 9 1 0
0 1 0 7 9 6 7 8 9 6 3 0 1
4 2 1 9 8 1 0
8 9 1 8 7 1 6 5 1 4 3 1 2 1 1
1 4 7 2 0 1 0
7 4 5 6 3 4 1 2 3 5 9 4 9
8 4 5 5 5 9 4 9 9
8 9 1 2 6 1 8 1 6 9 9
2 4 9 5 1 1 0 8 9
8 5 2 4 9 9 8 0
2 2 2 2 2 2 2 2 2 1 0 8 9 0

The sum of the across clues was 891873821817653.

There were 40 entries, 37 of which were correct. The randomly selected winners are:

  1. Laurence, who wins a £100 Maths Gear goody bag,
  2. Robert Hannan, who wins a Chalkdust T-shirt,
  3. James, who wins a Chalkdust T-shirt,
  4. Thomas Smith, who wins a Chalkdust T-shirt.

Well done to Laurence, Robert, James and Thomas, and thanks to everyone else who attempted the crossnumber. See you shortly in issue 11…

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Prize crossnumber, Issue 10

Our original prize crossnumber is featured on pages 48 and 49 of Issue 10.

Rules

  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, enter the sum of the across clues below by 2 February 2020. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 14 March 2020.

Correction: Clue 13A has been corrected to “49A reversed” instead of “49D reversed”.
Correction: Clue 38D has been corrected to “33A less than 39D” instead of “33A less than 39A”.
Clarificiation: The triangle in 6D is a right-angled triangle.
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Prize crossnumber, Issue 09

Our original prize crossnumber is featured on pages 54 and 55 of Issue 09.

Rules

  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, enter the sum of the across clues below by 9 September 2019. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 28 September 2019.

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Prize crossnumber, Issue 08

Our original prize crossnumber is featured on pages 54 and 55 of Issue 08.

Rules

  • Although many of the clues have multiple answers, there is only one solution to the completed crossnumber. As usual, no numbers begin with 0. Use of Python, OEIS, Wikipedia, etc. is advised for some of the clues.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Word DVD, a dodecaplex puzzle and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. The prizes have been provided by Maths Gear, a website that sells nerdy things worldwide. Find out more at mathsgear.co.uk
  • To enter, submit the sum of the across clues via this form by 2 February 2019. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 16 February 2019.

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