OFFSET
2,4
LINKS
Ivan Neretin, Table of n, a(n) for n = 2..10000
FORMULA
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
KEYWORD
nonn
AUTHOR
EXTENSIONS
Offset set to 2 by R. J. Mathar, Sep 15 2009
STATUS
approved