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A287166
Smallest number with exactly n representations as a sum of 7 nonzero squares or 0 if no such number exists.
12
7, 22, 31, 37, 45, 67, 55, 61, 69, 70, 79, 82, 94, 108, 85, 93, 103, 106, 111, 132, 109, 126, 139, 117, 147, 146, 130, 145, 144, 133, 153, 167, 141, 154, 160, 172, 159, 166, 187, 157, 177, 174, 175, 0, 178, 165
OFFSET
1,1
FORMULA
A025431(a(n)) = n for a(n) > 0.
EXAMPLE
a(1) = 7 because 7 is the smallest number with exactly 1 representation as a sum of 7 nonzero squares: 7 = 1^2 + 1^2 + 1^2 + 1^2 + 1^2 + 1^2 + 1^2;
a(2) = 22 because 22 is the smallest number with exactly 2 representations as a sum of 7 nonzero squares: 22 = 1^2 + 1^2 + 1^2 + 1^2 + 1^2 + 1^2 + 4^2 = 1^2 + 1^2 + 2^2 + 2^2 + 2^2 + 2^2 + 2^2, etc.
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 20 2017
STATUS
approved