5 December

Today's number is the number of ways that 35 can be written as the sum of distinct numbers, with none of the numbers in the sum being divisible by 9.
Clarification: By "numbers", I mean (strictly) positive integers. The sum of the same numbers in a different order is counted as the same sum: eg. 1+34 and 34+1 are not different sums. The trivial sum consisting of just the number 35 counts as a sum.


Show me a random puzzle
 Most recent collections 

Advent calendar 2020

Advent calendar 2019

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

List of all puzzles


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


Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2021