Click here to win prizes by solving the puzzle Advent calendar.
Click here to win prizes by solving the puzzle Advent calendar.


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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 Most recent collections 

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Coloured weights
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Cryptic crossnumber #2

Sunday Afternoon Maths LXV

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


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© Matthew Scroggs 2012–2019