A024171 Integer part of ((4th elementary symmetric function of 1,2,...,n)/(1+2+...+n)).

0, 0, 0, 2, 18, 77, 241, 623, 1406, 2868, 5415, 9608, 16203, 26188, 40830, 61720, 90827, 130548, 183773, 253942, 345116, 462042, 610231, 796034, 1026724, 1310578, 1656969, 2076457, 2580887, 3183486, 3898970, 4743648, 5735537, 6894474, 8242236, 9802664

Offset

1,4

Links

Ivan Neretin and Muniru A Asiru, Table of n, a(n) for n = 1..5000(Terms 1 through 36 from Ivan Neretin)

Formula

a(n) = floor( A000915(n-3)/A000217(n)). - R. J. Mathar, Sep 15 2009

a(n) = floor((1/2880)*(n - 3)*(n - 2)*(n - 1)*(15*n^3 + 15*n^2 - 10*n - 8)).

Maple

seq(floor((1/2880)*(n-3)*(n-2)*(n-1)*(15*n^3+15*n^2-10*n-8)), n=1..50); # Muniru A Asiru, May 19 2018

Mathematica

Table[Floor[1/2880 (n - 3) (n - 2) (n - 1) (15 n^3 + 15 n^2 - 10 n - 8)], {n, 36}] (* Ivan Neretin, May 19 2018 *)

Prog

(GAP) List([1..50], n->Int((1/2880)*(n-3)*(n-2)*(n-1)*(15*n^3+15*n^2-10*n-8))); # Muniru A Asiru, May 19 2018

Crossrefs

Sequence in context: A098817 A197093 A034473 * A056664 A213830 A323947

Adjacent sequences: A024168 A024169 A024170 * A024172 A024173 A024174

Keyword

nonn

Author

Clark Kimberling

Status

approved