|
%I M2776
%S 0,3,9,21,39,66,102,150,210,285,375,483,609,756,924,1116,1332,1575,
%T 1845,2145,2475,2838,3234,3666,4134,4641,5187,5775,6405,7080,7800,
%U 8568,9384,10251,11169,12141,13167,14250,15390
%N [ n(n+2)(2n-1)/8 ].
%D From a problem on p. 151 of J. Rec. Math., 7 (1975).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%F 3*A002623(n) for n>0. - M. F. Hasler, Sep 15 2009
%F G.f.:3*x/((x+1)*(x-1)^4) [From Maksym Voznyy (voznyy(AT)mail.ru), Aug 10 2009]
%Y Column 4 of triangle A094953.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, _Robert G. Wilson v_
|