A281967 Number of sets of exactly n positive integers <= n+4 having a square element sum.

1, 2, 3, 5, 8, 13, 19, 25, 34, 47, 58, 70, 92, 113, 130, 156, 194, 218, 246, 299, 343, 373, 430, 508, 543, 596, 701, 765, 813, 920, 1047, 1090, 1181, 1365, 1436, 1509, 1697, 1865, 1915, 2068, 2349, 2411, 2522, 2832, 3017, 3076, 3331, 3705, 3743, 3918, 4389

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Formula

a(n) = A281871(n+4,n).

Example

a(2) = 3: {1,3}, {3,6}, {4,5}.
a(3) = 5: {1,2,6}, {1,3,5}, {2,3,4}, {3,6,7}, {4,5,7}.
a(4) = 8: {1,2,5,8}, {1,2,6,7}, {1,3,4,8}, {1,3,5,7}, {1,4,5,6}, {2,3,4,7}, {2,3,5,6}, {4,6,7,8}.

Crossrefs

A diagonal of A281871.

Sequence in context: A301754 A120761 A355513 * A178741 A308929 A308994

Adjacent sequences: A281964 A281965 A281966 * A281968 A281969 A281970

Keyword

nonn

Author

Alois P. Heinz, Feb 03 2017

Status

approved