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A098307 Unsigned member r=-7 of the family of Chebyshev sequences S_r(n) defined in A092184. +0
1
0, 1, 7, 64, 567, 5041, 44800, 398161, 3538647, 31449664, 279508327, 2484125281, 22077619200, 196214447521, 1743852408487, 15498457228864, 137742262651287, 1224181906632721, 10879894897043200, 96694872166756081 (list; graph; listen)
OFFSET

0,3

COMMENT

((-1)^(n+1))*a(n) = S_{-7}(n), n>=0, defined in A092184.

LINKS

Index entries for sequences related to Chebyshev polynomials.

FORMULA

a(n)= 2*(T(n, 9/2)-(-1)^n)/11, with twice Chebyshev's polynomials of the first kind evaluated at x=9/2: 2*T(n, 9/2)=A056918(n)=((9+sqrt(77))^n + (9-sqrt(77))^n)/2^n.

a(n)= 9*a(n-1)-a(n-2)+2*(-1)^(n+1), n>=2, a(0)=0, a(1)=1.

a(n)= 8*a(n-1) + 8*a(n-2) - a(n-3), n>=3, a(0)=0, a(1)=1, a(2)=7.

G.f.: x*(1-x)/((1+x)*(1-9*x+x^2)) = x*(1-x)/(1-8*x-8*x^2+x^3) (from the Stephan link, see A092184).

CROSSREFS

Sequence in context: A027767 A055537 A159617 this_sequence A055995 A008787 A024095

Adjacent sequences: A098304 A098305 A098306 this_sequence A098308 A098309 A098310

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Oct 18 2004

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Last modified December 11 12:57 EST 2009. Contains 170656 sequences.


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