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A281971 Number of sets of exactly n positive integers <= n+8 having a square element sum. 2
1, 3, 7, 20, 49, 110, 227, 435, 786, 1358, 2259, 3621, 5627, 8538, 12655, 18318, 26049, 36487, 50236, 68131, 91412, 121207, 158659, 205768, 264786, 337240, 425738, 534408, 665866, 822789, 1011364, 1237211, 1502645, 1814854, 2184786, 2615980, 3114026, 3695678 (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+8,n).

EXAMPLE

a(2) = 7: {1,3}, {1,8}, {2,7}, {3,6}, {4,5}, {6,10}, {7,9}.

a(3) = 20: {1,2,6}, {1,3,5}, {1,4,11}, {1,5,10}, {1,6,9}, {1,7,8}, {2,3,4}, {2,3,11}, {2,4,10}, {2,5,9}, {2,6,8}, {3,4,9}, {3,5,8}, {3,6,7}, {4,5,7}, {4,10,11}, {5,9,11}, {6,8,11}, {6,9,10}, {7,8,10}.

CROSSREFS

A diagonal of A281871.

Sequence in context: A111974 A243100 A173400 * A230352 A271894 A066315

Adjacent sequences:  A281968 A281969 A281970 * A281972 A281973 A281974

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Feb 03 2017

STATUS

approved

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Last modified March 18 22:11 EDT 2019. Contains 321305 sequences. (Running on oeis4.)