A259395 a(n) = -3*n^2*(n-1)^4*(n+1)*(11*n^3+49*n^2-439*n+171).

0, 0, 15228, 705024, 1885680, -66355200, -792382500, -4986842112, -22516232256, -81696522240, -252908835300, -693126720000, -1723987588752, -3961019252736, -8517765880260, -17315965900800, -33541737120000, -62298041352192, -111515651966916, -193198552634880

Offset

0,3

Links

Table of n, a(n) for n=0..19.

M. P. Delest, Generating functions for column-convex polyominoes, J. Combin. Theory Ser. A 48 (1988), no. 1, pp. 12-31. See expression D in Theorem 16 page 29.

Index entries for linear recurrences with constant coefficients, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1).

Formula

G.f.: 324*x^2*(47+1659*x - 15531*x^2 - 156895*x^3 - 216255*x^4 - 17547*x^5 + 31451*x^6 + 3471*x^7) / (1-x)^11.

a(n) = 11*a(n-1) - 55*a(n-2) + 165*a(n-3) - 330*a(n-4) + 462*a(n-5) - 462*a(n-6) + 330*a(n-7) - 165*a(n-8) + 55*a(n-9) - 11*a(n-10) + a(n-11).

Maple

A259395:=n->-3*n^2*(n-1)^4*(n+1)*(11*n^3+49*n^2-439*n+171): seq(A259395(n), n=0..25); # Wesley Ivan Hurt, Jun 29 2015

Mathematica

Table[-3 n^2 (n - 1)^4 (n + 1) (11 n^3 + 49 n^2 - 439 n + 171), {n, 0, 23}]

Prog

(Magma) [-3*n^2*(n-1)^4*(n+1)*(11*n^3+49*n^2-439*n+171): n in [0..20]];

Crossrefs

Cf. A001105, A005435, A259364.

Sequence in context: A196495 A031623 A105924 * A233924 A115924 A251952

Adjacent sequences: A259392 A259393 A259394 * A259396 A259397 A259398

Keyword

sign,easy

Author

Vincenzo Librandi, Jun 26 2015

Status

approved