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A143508 G.f. satisfies: A(x) = 1 + x*A(x*A(x)^2)^2. 0
1, 1, 2, 9, 52, 372, 3058, 28074, 282028, 3059328, 35497672, 437499541, 5696752234, 78036803430, 1120687989348, 16823652188164, 263345788211608, 4289062071449610, 72543038644585822, 1271980596430351862 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

EXAMPLE

G.f. A(x) = 1 + x + 2*x^2 + 9*x^3 + 52*x^4 + 372*x^5 + 3058*x^6 +...

A(x)^2 = 1 + 2*x + 5*x^2 + 22*x^3 + 126*x^4 + 884*x^5 + 7149*x^6 +...

A(x*A(x)^2) = 1 + x + 4*x^2 + 22*x^3 + 156*x^4 + 1285*x^5 + 11886*x^6 +...

A(x*A(x)^2)^2 = 1 + 2*x + 9*x^2 + 52*x^3 + 372*x^4 + 3058*x^5 +...

PROG

(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=1+x*subst(A^2, x, x*A^2)); polcoeff(A, n)}

CROSSREFS

Sequence in context: A003584 A069271 A006152 * A052882 A143922 A110322

Adjacent sequences:  A143505 A143506 A143507 * A143509 A143510 A143511

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Aug 21 2008

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Last modified February 17 02:48 EST 2012. Contains 205978 sequences.