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Advent calendar 2018
11 December
All 2018 advent puzzles
~
More information
This puzzle is inspired by
a puzzle Woody showed me at MathsJam
.
Today's number is the number \(n\) such that $$\frac{216!\times215!\times214!\times...\times1!}{n!}$$ is a square number.
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By the same method as
this puzzle
, the answer is
108
.
Tags:
numbers
,
square numbers
,
factorials
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Tags
square roots
squares
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angles
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time
rectangles
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ave
integers
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mean
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volume
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colouring
crosswords
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rugby
fractions
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differentiation
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proportion
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coordinates
folding tube maps
xor
complex numbers
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triangle numbers
number
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medians
probability
calculus
polynomials
arrows
hexagons
consecutive numbers
quadratics
dominos
range
planes
routes
lists
digital products
area
even numbers
regular shapes
games
sums
unit fractions
cards
consecutive integers
tiling
star numbers
trigonometry
binary
cryptic clues
wordplay
the only crossnumber
dodecagons
powers
combinatorics
advent
remainders
functions
indices
means
taxicab geometry
multiplaction squares
clocks
square grids
people maths
scales
shape
sets
gerrymandering
albgebra
books
sport
geometric means
cubics
christmas
floors
median
chalkdust crossnumber
prime factors
tournaments
quadrilaterals
decahedra
ellipses
graphs
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