Advent calendar 2016

10 December

The smallest number that is equal to the sum of its digits multiplied by ten more than the sum of its digits.


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Advent calendar 2019

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

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perfect numbers crossnumbers chess digits remainders wordplay prime numbers ave games speed means gerrymandering chocolate unit fractions triangle numbers balancing sequences the only crossnumber circles calculus triangles cryptic crossnumbers planes rugby doubling bases odd numbers percentages functions algebra 3d shapes ellipses hexagons dodecagons folding tube maps clocks dice number fractions digital clocks floors scales pascal's triangle squares indices trigonometry polygons 2d shapes logic quadratics colouring division rectangles averages grids surds area coordinates advent books parabolas tiling spheres probability factors dates sums crossnumber median perimeter geometry range routes christmas irreducible numbers elections products lines integration arrows money star numbers factorials addition graphs time taxicab geometry coins regular shapes complex numbers square roots mean proportion partitions probabilty chalkdust crossnumber crosswords cards shapes square numbers menace differentiation numbers cryptic clues dominos sum to infinity shape multiplication volume cube numbers multiples people maths palindromes symmetry sport integers angles


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