Search: id:A106707 Results 1-1 of 1 results found. %I A106707 %S A106707 0,1,4,15,56,209,780,2911,10864,40545,151316,564719,2107560,7865521, %T A106707 29354524,109552575,408855776,1525870529,5694626340,21252634831,79315912984, %U A106707 296011017105,1104728155436,4122901604639,15386878263120,57424611447841 %V A106707 0,-1,-4,-15,-56,-209,-780,-2911,-10864,-40545,-151316,-564719,-2107560, -7865521, %W A106707 -29354524,-109552575,-408855776,-1525870529,-5694626340,-21252634831, -79315912984, %X A106707 -296011017105,-1104728155436,-4122901604639,-15386878263120,-57424611447841 %N A106707 First entry of the vector (M^n)v, where M is the 2 X 2 matrix [[0,-1], [1,4]] and v is the column vector [0,1]. %C A106707 Real Pisot roots (the eigenvalues of M): 2-sqrt(3)=0.267949, 2+sqrt(3)=3.73205. %H A106707 Index entries for sequences related to linear recurrences with constant coefficients %H A106707 Tanya Khovanova, Recursive Sequences %F A106707 a(n)=first entry of v[n], where v[n]=Mv[n-1], M is the 2 X 2 matrix [[0, -1], [1, 4]] and v[0] is the column vector [0,1]. G.f.=-x/(1-4x+x^2). a(n)=4a(n-1)-a(n-2); a(0)=0, a(1)=-1. %F A106707 a(n)=(1/6)*sqrt(3)*[2-sqrt(3)]^n-(1/6)*sqrt(3)*[2+sqrt(3)]^n, with n> =0 [From Paolo P. Lava (ppl(AT)spl.at), Oct 06 2008] %p A106707 a[0]:=0: a[1]:=-1: for n from 2 to 27 do a[n]:=4*a[n-1]-a[n-2] od: seq(a[n], n=0..27); %t A106707 M = {{0, -1}, {1, 4}} v[1] = {0, 1} v[n_] := v[n] = M.v[n - 1] a = Table[Abs[v[n][[1]]], {n, 1, 50}] %Y A106707 Cf. A001076, A001353. %Y A106707 Sequence in context: A077824 A010905 A001353 this_sequence A125905 A026030 A047038 %Y A106707 Adjacent sequences: A106704 A106705 A106706 this_sequence A106708 A106709 A106710 %K A106707 sign %O A106707 0,3 %A A106707 Roger L. Bagula (rlbagulatftn(AT)yahoo.com), May 30 2005 %E A106707 Edited by N. J. A. Sloane (njas(AT)research.att.com), Apr 30 2006 Search completed in 0.001 seconds