A281972 Number of sets of exactly n positive integers <= n+9 having a square element sum.
1, 3, 8, 26, 69, 166, 365, 750, 1446, 2646, 4645, 7856, 12852, 20411, 31626, 47910, 71022, 103342, 147982, 208554, 289572, 397140, 538319, 720965, 955716, 1255661, 1634233, 2108003, 2699453, 3431884, 4329465, 5426928, 6764353, 8377805, 10314695, 12640228
Offset: 0
Keywords
Examples
a(1) = 3: {1}, {4}, {9}. a(2) = 8: {1,3}, {1,8}, {2,7}, {3,6}, {4,5}, {5,11}, {6,10}, {7,9}.
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
Crossrefs
A diagonal of A281871.
Formula
a(n) = A281871(n+9,n).