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A281967
Number of sets of exactly n positive integers <= n+4 having a square element sum.
2
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
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
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Feb 03 2017
STATUS
approved