mscroggs
.co.uk
mscroggs
.co.uk
blog
puzzles
academic
talks
contact
subscribe
↓ ☰ ↓
subscribe
Loading image...
Advent calendar 2015
23 December
All 2015 advent puzzles
~
More information
This number is a prime number. If you treble it and add 16, the result is also prime. Repeating this will give 11 prime numbers in total (including the number itself).
Show answer
Hide answer
587
Tags:
numbers
,
prime numbers
Archive
Show me a random puzzle
Most recent collections
Advent calendar 2025
Advent calendar 2024
Advent calendar 2023
Advent calendar 2022
List of all puzzles
Tags
products
rectangles
chalkdust crossnumber
numbers
quadratics
perimeter
decahedra
gerrymandering
elections
matrices
books
integers
cards
sport
square grids
speed
surds
triangles
wordplay
quadrilaterals
pentagons
coordinates
clocks
polynomials
volume
scales
multiplaction squares
grids
star numbers
dice
floors
trigonometry
the only crossnumber
percentages
coins
planes
angles
digital clocks
powers
dates
christmas
games
neighbours
indices
median
consecutive integers
consecutive numbers
cubics
dodecagons
square roots
cube numbers
routes
lines
tiling
sequences
symmetry
prime numbers
complex numbers
combinatorics
digital products
polygons
logic
digits
differentiation
spheres
cryptic clues
advent
graphs
multiples
menace
circles
averages
area
mean
means
range
functions
unit fractions
people maths
prime factors
sums
balancing
regular shapes
shapes
sets
proportion
partitions
time
ellipses
binary
integration
shape
tournaments
probabilty
irreducible numbers
pascal's triangle
square numbers
algebra
perfect numbers
division
palindromes
odd numbers
crosswords
axes
even numbers
crossnumbers
triangle numbers
probability
geometric mean
xor
remainders
sum to infinity
expansions
colouring
factors
parabolas
rugby
chocolate
geometric means
geometry
albgebra
chess
money
ave
dominos
2d shapes
tangents
taxicab geometry
medians
multiplication
factorials
fractions
calculus
addition
squares
3d shapes
determinants
folding tube maps
number
cryptic crossnumbers
arrows
hexagons
bases
lists
doubling
Archive
Show me a random puzzle
▼ show ▼
▲ hide ▲
Most recent collections
Advent calendar 2025
Advent calendar 2024
Advent calendar 2023
Advent calendar 2022
List of all puzzles
Tags
cards
sums
folding tube maps
the only crossnumber
rugby
tournaments
perfect numbers
averages
consecutive integers
determinants
irreducible numbers
volume
surds
pentagons
geometric means
rectangles
integration
remainders
lists
grids
powers
shape
time
addition
regular shapes
cryptic crossnumbers
sport
prime factors
arrows
complex numbers
multiples
albgebra
mean
planes
sequences
digital clocks
functions
coins
means
dice
neighbours
angles
scales
people maths
number
quadrilaterals
gerrymandering
colouring
hexagons
dates
money
cubics
logic
polynomials
median
sets
trigonometry
crossnumbers
chess
circles
products
advent
perimeter
odd numbers
combinatorics
clocks
indices
factors
dodecagons
crosswords
prime numbers
quadratics
division
dominos
taxicab geometry
numbers
ave
square roots
triangle numbers
axes
expansions
unit fractions
digits
square numbers
palindromes
spheres
differentiation
multiplaction squares
books
xor
christmas
geometry
triangles
proportion
symmetry
probability
binary
elections
square grids
pascal's triangle
tangents
parabolas
routes
speed
chocolate
shapes
games
coordinates
sum to infinity
polygons
consecutive numbers
chalkdust crossnumber
ellipses
medians
floors
factorials
calculus
integers
cryptic clues
range
multiplication
balancing
matrices
tiling
algebra
lines
star numbers
decahedra
probabilty
digital products
even numbers
bases
cube numbers
graphs
menace
wordplay
squares
area
fractions
geometric mean
partitions
percentages
doubling
2d shapes
3d shapes
© Matthew Scroggs 2012–2026