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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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numbers
,
factorials
,
multiplication
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List of all puzzles
Tags
star numbers
pascal's triangle
decahedra
range
logic
triangles
rugby
multiplaction squares
cube numbers
integration
integers
quadratics
elections
tournaments
digital products
christmas
square roots
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sequences
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irreducible numbers
combinatorics
products
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consecutive integers
axes
matrices
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clocks
dates
chocolate
doubling
division
triangle numbers
ellipses
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dominos
balancing
unit fractions
square grids
arrows
shapes
hexagons
cards
expansions
games
factorials
floors
tangents
medians
cryptic crossnumbers
sums
tiling
money
scales
square numbers
coins
indices
trigonometry
advent
sport
algebra
people maths
complex numbers
partitions
chalkdust crossnumber
median
powers
multiplication
books
taxicab geometry
mean
surds
polynomials
digital clocks
coordinates
sum to infinity
parabolas
perfect numbers
volume
speed
3d shapes
sets
quadrilaterals
lines
differentiation
probabilty
means
prime factors
factors
ave
determinants
chess
numbers
routes
spheres
grids
palindromes
perimeter
averages
area
2d shapes
the only crossnumber
xor
crossnumbers
dice
odd numbers
angles
digits
squares
albgebra
calculus
dodecagons
crosswords
polygons
geometry
fractions
planes
cubics
folding tube maps
probability
circles
regular shapes
prime numbers
even numbers
symmetry
gerrymandering
percentages
neighbours
shape
cryptic clues
remainders
geometric means
wordplay
bases
multiples
consecutive numbers
binary
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graphs
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pentagons
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