Search: id:A058799 Results 1-1 of 1 results found. %I A058799 %S A058799 1,3,11,52,301,2055,16139,143196,1415821,15430835,183754199,2373373752, %T A058799 33043478329,493278801183,7859417340599,133116815989000, %U A058799 2388243270461401,45243505322777619,902481863185090979 %N A058799 Column 2 of A007754. %D A058799 Weisstein, Eric W. "Modular Group Gamma." http : // mathworld.wolfram.com/ ModularGroupGamma.html [From Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 02 2008] %F A058799 a(n) =(n+2)*a(n-1)-a(n-2) [with a(0)=1 and a(-1)=0] =A058798(n+1)-A058797(n+2) - Henry Bottomley (se16(AT)btinternet.com), Feb 28 2001 %F A058799 A signed version with a slightly different start may be obtained from the modular group Gamma: Let S = {{0, -1}, {1, 0}}; T = {{1, 1}, {0, 1}}; m(n)=T^n.S.m(m-1); v(0)={1,0}; v(n)=m(n).v(0); a(n)=v(n)[[1]]. [From Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 02 2008] %t A058799 Clear[S, T, M, v, n]; S = {{0, -1}, {1, 0}}; T = {{1, 1}, {0, 1}}; M[0] = T.S; M[n_] := M[n] = (MatrixPower[T, n].S).M[n - 1]; v[0] = {1, 0}; v[n_] := v[n] = M[n].v[0]; a = Table[v[n][[1]], {n, 0, 30}] [From Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Nov 02 2008] %Y A058799 Sequence in context: A007047 A129097 A014510 this_sequence A054362 A129833 A107958 %Y A058799 Adjacent sequences: A058796 A058797 A058798 this_sequence A058800 A058801 A058802 %K A058799 nonn %O A058799 0,2 %A A058799 Christian G. Bower (bowerc(AT)usa.net), Dec 02 2000 Search completed in 0.001 seconds