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A138331 C(n+5, 5)*(n+3)*(-1)^(n+1)*16/3. 0
-16, 128, -560, 1792, -4704, 10752, -22176, 42240, -75504, 128128, -208208, 326144, -495040, 731136, -1054272, 1488384, -2062032, 2808960, -3768688, 4987136, -6517280, 8419840, -10764000, 13628160, -17100720, 21280896, -26279568, 32220160, -39239552 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Fourth column of the triangle defined in A123588, seventh column of the triangle defined in A123583.

LINKS

Index entries for sequences related to Chebyshev polynomials.

Index to sequences with linear recurrences with constant coefficients, signature (-7,-21,-35,-35,-21,-7,-1).

FORMULA

a(n) = coefficient of x^6 in the polynomial 1 - T_(n+3)(x)^2, where T_n(x) is the n-th Chebyshev polynomial of the first kind.

G.f.: 16*(x-1)/(x+1)^7.

a(n) = (-1)^(n+1)*16*A040977(n).

a(n) = a(-n-5). - Bruno Berselli, Sep 13 2011

PROG

(MAGMA) [ Binomial(n+5, 5)*(n+3)*(-1)^(n+1)*16/3: n in [0..28] ];

(MAGMA) k:=3; [ Coefficients(1-ChebyshevT(n+k)^2)[2*k+1]: n in [0..28] ];

(PARI) for(n=0, 28, print1(polcoeff(taylor(16*(x-1)/(x+1)^7, x), n), ", "));

CROSSREFS

Cf. A007318 (Pascal's triangle), A123588, A123583, A040977.

Sequence in context: A004017 A167471 A153115 * A008535 A008416 A045651

Adjacent sequences:  A138328 A138329 A138330 * A138332 A138333 A138334

KEYWORD

sign,easy

AUTHOR

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Mar 15 2008

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Last modified February 15 08:49 EST 2012. Contains 205740 sequences.