A138332 C(n+7, 7)*(n+4)*(-1)^(n+1)*16.

-64, 640, -3456, 13440, -42240, 114048, -274560, 604032, -1235520, 2379520, -4356352, 7637760, -12899328, 21085440, -33488640, 51845376, -78450240, 116290944, -169206400, 242070400, -341003520, 473616000, -649284480, 879465600, -1178049600

Offset

0,1

Comments

Fifth column of the triangle defined in A123588, ninth column of the triangle defined in A123583.

Links

Table of n, a(n) for n=0..24.

Index entries for sequences related to Chebyshev polynomials.

Formula

a(n) = coefficient of x^8 in the polynomial 1 - T_(n+4)(x)^2, where T_n(x) is the n-th Chebyshev polynomial of the first kind.

G.f.: 64*(x-1)/(x+1)^9.

a(n) = (-1)^(n+1)*64*A053347(n).

Prog

(Magma) [ Binomial(n+7, 7)*(n+4)*(-1)^(n+1)*16: n in [0..24] ];
(Magma) k:=4; [ Coefficients(1-ChebyshevT(n+k)^2)[2*k+1]: n in [0..24] ];
(PARI) for(n=0, 24, print1(polcoeff(taylor(64*(x-1)/(x+1)^9, x), n), ", "));

Crossrefs

Cf. A007318 (Pascal's triangle), A123588, A123583, A053347.

Sequence in context: A067476 A179810 A303265 * A091083 A136950 A136957

Adjacent sequences: A138329 A138330 A138331 * A138333 A138334 A138335

Keyword

sign

Author

Klaus Brockhaus, Mar 15 2008

Status

approved