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Advent calendar 2015
17 December
All 2015 advent puzzles
~
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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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205
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factorials
,
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triangle numbers
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christmas
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taxicab geometry
squares
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people maths
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angles
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digital products
circles
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averages
chocolate
factors
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surds
multiplication
albgebra
speed
probability
books
axes
sets
geometric means
matrices
cryptic clues
range
cubics
colouring
routes
calculus
spheres
ave
means
powers
digital clocks
coins
dice
tangents
elections
sums
area
proportion
median
pentagons
hexagons
binary
dodecagons
3d shapes
unit fractions
medians
shape
division
integers
fractions
grids
square grids
prime numbers
menace
polygons
square numbers
algebra
volume
pascal's triangle
wordplay
folding tube maps
cryptic crossnumbers
sum to infinity
scales
quadratics
lines
dominos
digits
probabilty
balancing
rectangles
sequences
consecutive numbers
parabolas
integration
complex numbers
chalkdust crossnumber
coordinates
bases
sport
cube numbers
gerrymandering
2d shapes
doubling
partitions
multiples
odd numbers
lists
rugby
even numbers
planes
combinatorics
multiplaction squares
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clocks
numbers
prime factors
tournaments
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floors
crossnumbers
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tiling
regular shapes
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