Advent calendar 2015

17 December

In March, I posted the puzzle One Hundred Factorial, which asked how many zeros 100! ends with.
What is the smallest number, n, such that n! ends with 50 zeros?


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Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

Sunday Afternoon Maths LXV

Cryptic crossnumber #1
Breaking Chocolate
Square and cube endings

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


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© Matthew Scroggs 2019