Search: id:A057091 Results 1-1 of 1 results found. %I A057091 %S A057091 1,8,72,640,5696,50688,451072,4014080,35721216,317882368,2828828672, %T A057091 25173688320,224020135936,1993550594048,17740565839872,157872931471360, %U A057091 1404907978489856,12502247279689728,111257242065436672 %N A057091 Scaled Chebyshev U-polynomials evaluated at i*sqrt(2). Generalized Fibonacci sequence. %C A057091 a(n) gives the length of the word obtained after n steps with the substitution rule 0->1^8, 1->(1^8)0, starting from 0. The number of 1's and 0's of this word is 8*a(n-1) and 8*a(n-2), resp. %D A057091 A. F. Horadam, Special properties of the sequence W_n(a,b; p,q), Fib. Quart., 5.5 (1967), 424-434. Case n->n+1, a=0,b=1; p=8, q=8. %D A057091 W. Lang, On polynomials related to powers of the generating function of Catalan's numbers, Fib. Quart. 38,5 (2000) 408-419; Eqs.(39) and (45),rhs, m=8. %H A057091 Index entries for sequences related to linear recurrences with constant coefficients %H A057091 Tanya Khovanova, Recursive Sequences %H A057091 Index entries for sequences related to Chebyshev polynomials. %F A057091 a(n) = 8*(a(n-1)+a(n-2)), a(-1)=0, a(0)=1. %F A057091 a(n)= S(n, i*2*sqrt(2))*(-i*2*sqrt(2))^n with S(n, x) := U(n, x/2), Chebyshev's polynomials of the 2nd kind, A049310. %F A057091 G.f.: 1/(1-8*x-8*x^2). %F A057091 a(n)=Sum_{k, 0<=k<=n}7^k*A063967(n,k) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 03 2006 %F A057091 a(n)=-(1/6)*sqrt(6)*[4-2*sqrt(6)]^n+(1/2)*[4+2*sqrt(6)]^n+(1/6)*[4+2*sqrt(6)]^n*sqrt(6)+(1/ 2) *[4-2*sqrt(6)]^n, with n>=0 - Paolo P. Lava (ppl(AT)spl.at), Jul 08 2008 %o A057091 (Other) sage: [lucas_number1(n,8,-8) for n in xrange(0, 20)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 25 2009] %Y A057091 Sequence in context: A052379 A158798 A062541 this_sequence A156566 A055275 A155198 %Y A057091 Adjacent sequences: A057088 A057089 A057090 this_sequence A057092 A057093 A057094 %K A057091 nonn,easy %O A057091 0,2 %A A057091 Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Aug 11 2000 Search completed in 0.001 seconds