# Advent calendar 2018

## Archive

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#### Sunday Afternoon Maths LXVII

Coloured weightsNot Roman numerals

#### Advent calendar 2018

#### Sunday Afternoon Maths LXVI

Cryptic crossnumber #2#### Sunday Afternoon Maths LXV

Cryptic crossnumber #1Breaking Chocolate

Square and cube endings

List of all puzzles

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coins factorials polygons speed sport cards square numbers balancing bases factors sum to infinity dice parabolas christmas wordplay chess doubling surds multiples volume indices proportion cube numbers sequences dodecagons regular shapes quadratics squares star numbers addition spheres dates rectangles fractions algebra number planes area geometry probability folding tube maps cryptic clues digits sums percentages triangle numbers trigonometry partitions symmetry rugby graphs means integers floors ellipses angles crossnumbers 3d shapes scales odd numbers differentiation taxicab geometry division complex numbers shapes perimeter cryptic crossnumbers crosswords routes colouring functions unit fractions circles grids money 2d shapes averages square roots clocks integration numbers pascal's triangle lines perfect numbers hexagons ave calculus chalkdust crossnumber mean advent multiplication coordinates menace time people maths palindromes games remainders shape triangles books arrows chocolate logic irreducible numbers probabilty prime numbers## 18 December

There are 6 terms in the expansion of \((x+y+z)^2\):

$$(x+y+z)^2=x^2+y^2+z^2+2xy+2yz+2xz$$
Today's number is number of terms in the expansion of \((x+y+z)^{16}\).