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