This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A153852 Nonzero coefficients of g.f.: A(x) = G(G(x)) where G(x) = x + G(G(x))^3 is the g.f. of A153851. 4
 1, 2, 15, 165, 2213, 33693, 561867, 10053141, 190489374, 3788856192, 78613758564, 1693737431667, 37760673462507, 868775517322730, 20583609967109565, 501340716386677815, 12535093359045980151, 321360932709750239226 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA G.f.: A(x) = Sum_{n>=0} a(2n+1)*x^(2n+1) = G(G(x)) where G(x) is the g.f. of A153851. G.f.: A(x) = G(x) + H(x)^3 where G(x) is the g.f. of A153851 and H(x) is the g.f. of A153853. EXAMPLE G.f.: A(x) = x + 2*x^3 + 15*x^5 + 165*x^7 + 2213*x^9 +... A(x)^3 = x^3 + 6*x^5 + 57*x^7 + 683*x^9 + 9474*x^11 + 145815*x^13 +... A(x) = G(G(x)) where G(x) = x + x^3 + 6*x^5 + 57*x^7 + 683*x^9 + 9474*x^11 +... Let H(x) = g.f. of A153853, then A(x) = G(x) + H(x)^3 where H(x) = x + 3*x^3 + 27*x^5 + 339*x^7 + 5067*x^9 + 84738*x^11 +... H(x)^3 = x^3 + 9*x^5 + 108*x^7 + 1530*x^9 + 24219*x^11 +... PROG (PARI) {a(n)=local(G=x+O(x^(2*n+1))); for(i=0, n, G=serreverse(x-G^3)); polcoeff(subst(G, x, G), 2*n-1)} CROSSREFS Cf. A153851, A153853, A153854, A153850. Sequence in context: A259608 A317278 A140809 * A177396 A324151 A262035 Adjacent sequences:  A153849 A153850 A153851 * A153853 A153854 A153855 KEYWORD nonn AUTHOR Paul D. Hanna, Jan 21 2009 EXTENSIONS Formula corrected by Paul D. Hanna, Dec 07 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 22 18:53 EDT 2019. Contains 323481 sequences. (Running on oeis4.)