A399202 - OEIS

A399202

a(n) is the smallest nonnegative integer k where there are exactly n nonnegative integer solutions to x^2 + y^2 = k.

3, 0, 1, 50, 25, 1250, 325, 31250, 1105, 8450, 4225, 19531250, 5525, 488281250, 203125, 211250, 27625, 305175781250, 71825, 7629394531250, 138125, 5281250, 2640625, 4768371582031250, 160225, 35701250, 17850625, 2442050, 1221025, 74505805969238281250, 1795625, 1862645149230957031250

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OFFSET

0,1

COMMENTS

a(n) is the smallest nonnegative k such that A000925(k) = n.

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..100

FORMULA

For n >= 2, a(n) = min(A018782(n), A018782(n-1)) if n is even, and a(n) = 2*A018782(n) if n is odd.

EXAMPLE

n | A018782 | a(n)

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