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 A120056 G.f.: A(x) satisfies: A(x*A(x)) = A(x)^2/(1+x). 1
 1, 1, 1, 3, 14, 91, 737, 7096, 78766, 987842, 13797282, 212285511, 3567147508, 65001800879, 1276876433466, 26901212485406, 605144725934525, 14477882030623891, 367106501841287465, 9834718739970491625 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS EXAMPLE A(x) = 1 + x + x^2 + 3*x^3 + 14*x^4 + 91*x^5 + 737*x^6 +... A(x)^2 = 1 + 2*x + 3*x^2 + 8*x^3 + 35*x^4 + 216*x^5 + 1693*x^6 +... A(x*A(x)) = 1 + x + 2*x^2 + 6*x^3 + 29*x^4 + 187*x^5 + 1506*x^6 +... PROG (PARI) {a(n)=local(A); if(n<1, n==0, A=1+x; for(i=1, n, A=subst(A, x, x*A+x*O(x^n))*(1+x)/A); polcoeff(A, n))} CROSSREFS Cf. A088792. Sequence in context: A202294 A029767 A215475 * A125788 A183611 A101220 Adjacent sequences:  A120053 A120054 A120055 * A120057 A120058 A120059 KEYWORD nonn AUTHOR Paul D. Hanna, Jun 05 2006 STATUS approved

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Last modified May 19 10:20 EDT 2013. Contains 225429 sequences.