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A141371
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G.f. satisfies: A(x) = x + A(A(A(x))^2).
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4
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1, 1, 4, 25, 190, 1648, 15700, 160834, 1747372, 19945264, 237585064, 2938737760, 37602695500, 496263658816, 6739460289568, 94002095361937, 1344557294558722, 19696746902333368, 295199862739677892, 4522172757314573464
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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FORMULA
| G.f. satisfies: A( x - A(A(x)^2) ) = x.
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EXAMPLE
| G.f.: A(x) = x + x^2 + 4*x^3 + 25*x^4 + 190*x^5 + 1648*x^6 + 15700*x^7 +...
The series reversion of A(x) = x - A(A(x)^2), where
A(A(x)^2) = x^2 + 2*x^3 + 10*x^4 + 62*x^5 + 472*x^6 + 4052*x^7 + 38227*x^8 +...
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PROG
| (PARI) {a(n)=local(A=x+x^2); for(i=1, n, A=x+subst(A, x, subst(A^2, x, A+x*O(x^n)))); polcoeff(A, n)}
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CROSSREFS
| Cf. A141370, A141372.
Sequence in context: A135147 A175913 A064063 * A199494 A171791 A060908
Adjacent sequences: A141368 A141369 A141370 * A141372 A141373 A141374
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KEYWORD
| nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Jun 28 2008
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