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A103768
a(n) = (29*3^n - 18(n + 3)*2^n + 6n^2 + 24n + 27)/12.
1
0, 0, 6, 46, 228, 930, 3406, 11682, 38412, 122806, 385182, 1192254, 3656452, 11141178, 33791934, 102161962, 308156748, 928008846, 2791497262, 8390220006, 25203689700, 75680274610, 227185526766, 681858569586, 2046204853708
OFFSET
0,3
FORMULA
a(n) = A078341(n, 3) = 3a(n-1)+n*A095151(n-1).
G.f.: -2*x^2*(x^3-4*x^2+7*x-3) / ((x-1)^3*(2*x-1)^2*(3*x-1)). - Colin Barker, Sep 13 2014
MATHEMATICA
Table[(29*3^n-18(n+3)2^n+6n^2+24n+27)/12, {n, 40}] (* or *) LinearRecurrence[ {10, -40, 82, -91, 52, -12}, {0, 0, 6, 46, 228, 930}, 40] (* Harvey P. Dale, Aug 31 2018 *)
PROG
(PARI) concat([0, 0], Vec(-2*x^2*(x^3-4*x^2+7*x-3)/((x-1)^3*(2*x-1)^2*(3*x-1)) + O(x^100))) \\ Colin Barker, Sep 13 2014
CROSSREFS
Sequence in context: A154651 A327935 A079910 * A325947 A240779 A073507
KEYWORD
nonn,easy
AUTHOR
Henry Bottomley, Feb 15 2005
STATUS
approved