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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
OFFSET
2,4
LINKS
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 A374585 A146608
KEYWORD
nonn
EXTENSIONS
Offset changed to 2 by R. J. Mathar, Sep 15 2009
STATUS
approved