A223728 Multiplicities for A223727: primitive sums of four distinct nonzero squares.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 2, 3, 2, 1, 1, 1, 3, 2, 1, 3, 1, 1, 1, 2, 1, 1, 2, 1, 5, 1, 2, 3, 1, 1, 2, 3, 1, 2, 1, 1, 2, 4, 2, 1, 2, 3, 1, 5, 2, 2, 2, 2, 2, 4, 3, 1, 4, 1, 1, 4, 2, 2, 2, 5, 3, 1, 6, 3, 3, 1, 2, 1, 1, 4, 4, 2, 5, 1, 3, 7, 3, 2

Offset: 1

Author

Wolfdieter Lang, Mar 27 2013

Keywords

• nonn

Comments

A223728(n) has a(n) different primitive representations as sum of four distinct nonzero squares, n>=1.

Examples

			a(16) = 3 because A223727(16) = 78 has three s-quadruples, namely [1, 2, 3, 8], [1, 4, 5, 6] and [2, 3, 4, 7].
a(23) = 2 from A223727(23) =  90 with s-quadruples [1, 2, 6, 7] and [1, 3, 4, 8].
		

Crossrefs

Cf. A223727, A223726.

Formula

a(n) = k if there are k different solutions for A223728(n) = sum(s(j)^2, j=1..4), with 0 < s(1) < s(2) < s(3) < s(4) and gcd(s(1),s(2),s(3),s(4)) = 1.