Click here to win prizes by solving the puzzle Advent calendar.
Click here to win prizes by solving the puzzle Advent calendar.



Lots of ones

Is any of the numbers 11, 111, 1111, 11111, ... a square number?

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If you enjoyed this puzzle, check out Sunday Afternoon Maths LIII,
puzzles about numbers, or a random puzzle.


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Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

Sunday Afternoon Maths LXV

Cryptic crossnumber #1
Breaking Chocolate
Square and cube endings

List of all puzzles


grids fractions balancing 2d shapes rugby volume cards perimeter ellipses triangles taxicab geometry angles differentiation games integers rectangles routes coordinates polygons sum to infinity factors complex numbers regular shapes symmetry means dice mean money colouring planes star numbers 3d shapes sums partitions multiplication people maths bases cryptic crossnumbers indices trigonometry christmas percentages proportion dates ave triangle numbers calculus probabilty folding tube maps parabolas clocks digits speed chalkdust crossnumber doubling unit fractions scales algebra shapes integration squares functions averages number irreducible numbers probability cryptic clues chess prime numbers arrows advent square roots lines wordplay sport perfect numbers spheres hexagons square numbers remainders graphs geometry floors shape cube numbers factorials odd numbers books quadratics palindromes multiples sequences menace numbers division circles chocolate area crosswords surds time addition coins dodecagons pascal's triangle crossnumbers logic


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