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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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xor
books
averages
regular shapes
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cryptic crossnumbers
expansions
number
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chalkdust crossnumber
square grids
grids
axes
geometric means
speed
decahedra
rugby
trigonometry
shapes
sets
volume
percentages
planes
digital clocks
menace
star numbers
consecutive numbers
geometry
multiplaction squares
sport
elections
square roots
dates
tiling
functions
colouring
wordplay
ellipses
integers
odd numbers
proportion
even numbers
squares
taxicab geometry
tournaments
unit fractions
dodecagons
binary
coordinates
sums
probabilty
addition
digital products
christmas
parabolas
medians
gerrymandering
products
cryptic clues
doubling
division
integration
spheres
dominos
3d shapes
folding tube maps
chocolate
algebra
means
area
albgebra
coins
polynomials
crosswords
remainders
circles
multiplication
consecutive integers
advent
mean
chess
pascal's triangle
palindromes
factors
graphs
shape
angles
determinants
ave
calculus
dice
perimeter
digits
scales
irreducible numbers
floors
lines
games
time
complex numbers
sequences
polygons
sum to infinity
indices
tangents
bases
cubics
fractions
crossnumbers
differentiation
powers
triangles
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arrows
geometric mean
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logic
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prime numbers
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