# Crossnumber winners

300

Before we get on to winners, here is the solution of the Chalkdust prize crossnumber #1:

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

The sum of the across clues was $13 895 815 379$.

### Picking the Winners

We received $75$ entries of which $57$ were correct.

As the deadline for the crossnumber was Pi Approximation Day, we decided to assign each correct answer a number from 0 to 56, then use the digit of pi (expanded in base 57 (the number of correct entries)), to decide the winner (and the following digits for the runners up).

92 is the first number which is an answer to a crossnumber clue to appear in the decimal expansion of pi, so we decided to use the the 92nd digit of $\pi_{57}$ to decide the winner and the following digits to decide the runners up.

The digits in the base 57 expansion of pi starting with the 92nd digit are:*

$$5,5,25,48,20,47,38,17,45,14$$

So the winner of £100 is entry number $5$ and entry numbers $25$, $48$ and $20$ win the runners up prizes. This gives the following winners:

Joshua Engels

#### Runners Up (Chalkdust t-shirts)

Chris Spath
Lorenzo Anselmetti
Stephen Haas

Thank-you to everyone who entered the crossnumber competition. The competition will return in issue 2 of Chalkdust…

*If there is a mistake in the digits generated in this blog post, then the winners published here will remain the winners.

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