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A024169
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Integer part of ((2nd elementary symmetric function of 1,2,...,n)/(1+2+...+n)).
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1
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0, 0, 1, 3, 5, 8, 11, 15, 19, 24, 29, 34, 41, 47, 54, 62, 70, 79, 88, 98, 108, 119, 130, 141, 154, 166, 179, 193, 207, 222, 237, 253, 269, 286, 303, 320, 339, 357, 376, 396, 416, 437, 458, 480, 502
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OFFSET
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1,4
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LINKS
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FORMULA
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G.f.: x^3*(-1-x-x^5-2*x^7+x^4+x^8)/((x^2+1) * (1+x+x^2) * (x^4-x^2+1) * (x-1)^3). (End)
a(n) = floor((1/12)*(n - 1)*(3*n + 2)). - Ivan Neretin, May 19 2018
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MAPLE
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seq(floor((1/12)*(n-1)*(3*n+2)), n=1..50); # Muniru A Asiru, May 19 2018
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MATHEMATICA
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Table[Floor[1/12 (n - 1) (3 n + 2)], {n, 45}] (* Ivan Neretin, May 19 2018 *)
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PROG
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(GAP) List([1..50], n->Int((1/12)*(n-1)*(3*n+2))); # Muniru A Asiru, May 19 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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