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A281870 Number of sets of exactly ten positive integers <= n having a square element sum. 2
0, 1, 5, 16, 58, 171, 434, 1030, 2259, 4645, 9071, 16927, 30354, 52586, 88351, 144425, 230347, 359329, 549338, 824505, 1216843, 1768278, 2533124, 3581117, 5000891, 6904149, 9430598, 12753622, 17086885, 22692075, 29887626, 39058827, 50669397, 65274492, 83535475 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 10..1000

EXAMPLE

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

a(12) = 5: {1,2,3,4,5,7,9,10,11,12}, {1,2,3,4,6,7,8,10,11,12}, {1,2,3,5,6,7,8,9,11,12}, {1,2,4,5,6,7,8,9,10,12}, {1,3,4,5,6,7,8,9,10,11}.

MAPLE

b:= proc(n, i, t) option remember;

      `if`(i<t, 0, `if`(n=0, `if`(t=0, 1, 0),

      `if`(t<1 or n<t*(t+1)/2 or n>(t+1)*(2*i-t)/2, 0,

      `if`(i>n, 0, b(n-i, i-1, t-1))+b(n, i-1, t))))

    end:

a:= proc(n) option remember; `if`(n<0, 0, a(n-1)+add(

       b(j^2-n, n-1, 9), j=isqrt(n-45)..isqrt(10*n-45)))

    end:

seq(a(n), n=10..60);

CROSSREFS

Column k=10 of A281871.

Sequence in context: A057553 A226973 A006217 * A116914 A047103 A226897

Adjacent sequences:  A281867 A281868 A281869 * A281871 A281872 A281873

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Feb 01 2017

STATUS

approved

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Last modified March 19 13:29 EDT 2019. Contains 321330 sequences. (Running on oeis4.)