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A024173 Integer part of ((4th elementary symmetric function of 1,2,..,n)/(2nd elementary symmetric function of 1,2,...,n)). 1
0, 0, 0, 3, 9, 21, 41, 72, 119, 185, 275, 395, 549, 744, 987, 1285, 1645, 2076, 2586, 3185, 3882, 4688, 5612, 6667, 7863, 9213, 10731, 12428, 14318, 16416, 18737, 21295, 24106, 27187, 30553, 34223, 38214, 42543, 47231, 52295, 57756, 63633, 69948, 76721 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,4

LINKS

Ivan Neretin, Table of n, a(n) for n = 2..10000

FORMULA

a(n)= floor(A000915(n-3)/A000914(n-1)). - R. J. Mathar, Sep 15 2009

a(n) = floor((1/240) * (n-3) * (n-2) * (15*n^3 + 15*n^2 - 10*n - 8) / (2 + 3*n)). - Ivan Neretin, May 19 2018

EXAMPLE

a(4) = floor(24/35) = 0; a(5) = floor(274/85) = 3. - R. J. Mathar, Sep 15 2009

MAPLE

seq(floor((1/240)*(n-3)*(n-2)*(15*n^3+15*n^2-10*n-8)/(3*n+2)), n=2..50); # Muniru A Asiru, May 19 2018

MATHEMATICA

Table[Floor[1/240 (n - 3) (n - 2) (15 n^3 + 15 n^2 - 10 n - 8)/ (2 + 3 n)], {n, 2, 45}] (* Ivan Neretin, May 19 2018 *)

PROG

(GAP) List([2..50], n->Int((1/240)*(n-3)*(n-2)*(15*n^3+15*n^2-10*n-8)/(3*n+2))); # Muniru A Asiru, May 19 2018

CROSSREFS

Sequence in context: A059774 A064999 A100135 * A097119 A146608 A161214

Adjacent sequences:  A024170 A024171 A024172 * A024174 A024175 A024176

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

Offset changed to 2 by R. J. Mathar, Sep 15 2009

STATUS

approved

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Last modified October 22 19:53 EDT 2019. Contains 328319 sequences. (Running on oeis4.)