Search: id:A121012 Results 1-1 of 1 results found. %I A121012 %S A121012 1,120,14522,1757157,212616011,25726537289,282991910191,34242021133072, %T A121012 4143284557101842,501337431409322440,667280121205808184436, %U A121012 80740894665902790257970,9769648254574237621422382 %N A121012 Numerators of partial alternating sums of Catalan numbers scaled by powers of 1/(11^2) = 1/121. %C A121012 Denominators are given under A121013. %C A121012 This is the second member (p=2) of the fourth (normalized) p-family of partial sums of normalized scaled Catalan series CsnIV(p):=sum(((-1)^k)*C(k)/ L(2*p+1)^(2*k),k=0..infinity) with limit L(2*p+1)*(-F(2*p+2) + F(2*p+1)*phi) = L(2*p+1)/phi^(2*p+1), with C(n)=A000108(n) (Catalan), F(n)= A000045(n) (Fibonacci), L(n) = A000032(n) (Lucas) and phi:=(1+sqrt(5))/2 (golden section). %C A121012 The partial sums of the above mentioned fourth p-family are rIV(p;n):=sum(((-1)^k)*C(k)/ L(2*p+1)^(2*k),k=0..n), n>=0, for p=1,... %C A121012 For more details on this p-family and the other three ones see the W. Lang link under A120996. %H A121012 W. Lang: Rationals r(n), limit. %F A121012 a(n)=numerator(r(n)) with r(n) := rIV(p=2,n) = sum(((-1)^k)*C(k)/L(2*2+1)^(2*k), k=0..n), with L(5)=11 and C(k):=A000108(k) (Catalan). The rationals r(n) are given in lowest terms. %e A121012 Rationals r(n): [1, 120/121, 14522/14641, 1757157/1771561, %e A121012 212616011/214358881, 25726537289/25937424601,...]. %p A121012 The limit lim_{n->infinity} (r(n) := rIV(2;n)) = 11*(-8 + 5*phi) = 11/ phi^5 = 0.9918693812443 (maple10, 10 digits). %Y A121012 The first member is A120794/A120785. The third member is A121498/A121499. %Y A121012 Sequence in context: A104592 A135379 A059063 this_sequence A151985 A105188 A151604 %Y A121012 Adjacent sequences: A121009 A121010 A121011 this_sequence A121013 A121014 A121015 %K A121012 nonn,frac,easy %O A121012 0,2 %A A121012 Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Aug 16 2006 Search completed in 0.001 seconds