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A119685
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G.f. satisfies: A(x) = x + A(x^2/(1-x)^2).
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0
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1, 1, 2, 4, 8, 17, 38, 88, 208, 497, 1194, 2877, 6948, 16821, 40846, 99539, 243536, 598353, 1476370, 3657883, 9098420, 22713077, 56887062, 142897576, 359879600, 908373713, 2297266554, 5819357841, 14762051140, 37491373173, 95311970590
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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EXAMPLE
| A(x) = x + x^2 + 2*x^3 + 4*x^4 + 8*x^5 + 17*x^6 + 38*x^7 + 88*x^8 +...
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PROG
| (PARI) {a(n)=local(F=x^2/(1-x+x*O(x^n))^2, A=x); if(n<1, 0, for(i=1, #binary(n), A=x+subst(A, x, F)); polcoeff(A, n))}
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CROSSREFS
| Cf. A119262.
Sequence in context: A107597 A082499 A100131 * A025276 A006461 A003007
Adjacent sequences: A119682 A119683 A119684 * A119686 A119687 A119688
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KEYWORD
| nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Jun 08 2006
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