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A281968 Number of sets of exactly n positive integers <= n+5 having a square element sum. 2
1, 2, 4, 8, 14, 24, 39, 60, 86, 121, 171, 228, 294, 387, 499, 614, 762, 953, 1152, 1362, 1654, 1979, 2280, 2678, 3167, 3628, 4117, 4798, 5498, 6109, 6968, 7967, 8824, 9793, 11127, 12382, 13462, 15088, 16845, 18230, 19981, 22294, 24272, 26047, 28849, 31616 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

FORMULA

a(n) = A281871(n+5,n).

EXAMPLE

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

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

a(4) = 14: {1,2,4,9}, {1,2,5,8}, {1,2,6,7}, {1,3,4,8}, {1,3,5,7}, {1,4,5,6}, {1,7,8,9}, {2,3,4,7}, {2,3,5,6}, {2,6,8,9}, {3,5,8,9}, {3,6,7,9}, {4,5,7,9}, {4,6,7,8}.

CROSSREFS

A diagonal of A281871.

Sequence in context: A053800 A262968 A261203 * A091774 A280874 A243815

Adjacent sequences:  A281965 A281966 A281967 * A281969 A281970 A281971

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Feb 03 2017

STATUS

approved

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Last modified February 16 12:48 EST 2019. Contains 320163 sequences. (Running on oeis4.)