Search: id:A057089 Results 1-1 of 1 results found. %I A057089 %S A057089 1,6,42,288,1980,13608,93528,642816,4418064,30365280,208700064, %T A057089 1434392064,9858552768,67757668992,465697330560,3200729997312, %U A057089 21998563967232,151195763787264,1039165966526976,7142170381885440 %N A057089 Scaled Chebyshev U-polynomials evaluated at i*sqrt(6)/2. Generalized Fibonacci sequence. %C A057089 a(n) gives the length of the word obtained after n steps with the substitution rule 0->1^6, 1->(1^6)0, starting from 0. The number of 1's and 0's of this word is 6*a(n-1) and 6*a(n-2), resp. %D A057089 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=6, q=6. %D A057089 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=6. %H A057089 Index entries for sequences related to linear recurrences with constant coefficients %H A057089 Tanya Khovanova, Recursive Sequences %H A057089 Index entries for sequences related to Chebyshev polynomials. %F A057089 a(n) = 6*(a(n-1)+a(n-2)), a(-1)=0, a(0)=1. %F A057089 a(n)= S(n, i*sqrt(6))*(-i*sqrt(6))^n with S(n, x) := U(n, x/2), Chebyshev's polynomials of the 2nd kind, A049310. %F A057089 G.f.: 1/(1-6*x-6*x^2). %F A057089 a(n)=Sum_{k, 0<=k<=n}5^k*A063967(n,k) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 03 2006 %F A057089 a(n)=-(1/30)*sqrt(15)*[3-sqrt(15)]^(n+1)+(1/30)*sqrt(15)*[3+sqrt(15)]^(n+1), with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), Nov 20 2008] %o A057089 (Other) sage: [lucas_number1(n,6,-6) for n in xrange(1, 21)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 24 2009] %Y A057089 Sequence in context: A062310 A105482 A157335 this_sequence A110711 A156361 A055272 %Y A057089 Adjacent sequences: A057086 A057087 A057088 this_sequence A057090 A057091 A057092 %K A057089 nonn,easy %O A057089 0,2 %A A057089 Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Aug 11 2000 Search completed in 0.002 seconds