# Advent calendar 2015

## 23 December

This number is a prime number. If you treble it and add 16, the result is also prime. Repeating this will give 11 prime numbers in total (including the number itself).

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This number is a prime number. If you treble it and add 16, the result is also prime. Repeating this will give 11 prime numbers in total (including the number itself).

Not Roman numerals

Breaking Chocolate

Square and cube endings

List of all puzzles