Four-digit numbers
I have found a 3-digit perfect square, a 3-digit perfect cube and a 4-digit triangular number that between them use 10 different digits, with no leading zero. (Triangular numbers are those that fit the formula n(n+1)/2, like 1, 3, 6, 10, 15.)
I have also found a 3-digit perfect square, a 3-digit triangular number and a 4-digit perfect cube that between them use 10 different digits, with no leading zero.
What are my two 4-digit numbers?
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Answer to 1645 Neighbourhood watch: the house number is 32 The winner Alan Beasley of Leominster, Herefordshire, UK



