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A024172
Integer part of ((3rd elementary symmetric function of 1,2,..,n)/(2nd elementary symmetric function of 1,2,...,n)).
1
0, 0, 1, 2, 4, 6, 8, 10, 13, 16, 20, 24, 28, 33, 38, 43, 48, 54, 60, 67, 74, 81, 89, 97, 105, 113, 122, 131, 141, 151, 161, 172, 183, 194, 205, 217, 229, 242, 255, 268, 282, 296, 310, 324
OFFSET
2,4
LINKS
FORMULA
a(n) = floor( A001303(n-2)/A000914(n-1) ). - R. J. Mathar, Sep 15 2009
Empirical g.f.: x^4*(x^4-x^3+x^2-x+1)*(x^5-x^3-x^2-x-1) / ((x-1)^3*(x^2+x+1)*(x^6+x^3+1)). - Colin Barker, Aug 16 2014
a(n) = floor((1/2)*(n - 2)*n*(n + 1)/(3*n + 2)).
EXAMPLE
a(3) = floor(6/11) = 0; a(4) = floor(50/35) = 1. - R. J. Mathar, Sep 15 2009
MAPLE
seq(floor((1/2)*n*(n-2)*(n+1)/(3*n+2)), n=2..50); # Muniru A Asiru, May 19 2018
MATHEMATICA
Table[Floor[1/2 (n - 2) n (n + 1)/ (3 n + 2)], {n, 2, 45}] (* Ivan Neretin, May 19 2018 *)
PROG
(GAP) List([2..50], n->Int((1/2)*n*(n-2)*(n+1)/(3*n+2))); # Muniru A Asiru, May 19 2018
CROSSREFS
Sequence in context: A302648 A269746 A056827 * A233735 A085577 A331130
KEYWORD
nonn
EXTENSIONS
Offset set to 2 by R. J. Mathar, Sep 15 2009
STATUS
approved