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A144005 E.g.f. A(x) satisfies: A(x) = 1 + Series_Reversion( Integral A(-x) dx ). 1
1, 1, 1, 2, 7, 33, 201, 1479, 12842, 127952, 1440989, 18070767, 249766088, 3769280801, 61654447712, 1085974748430, 20485430748783, 411839042136379, 8786499316562396, 198174104269740313, 4708919322491690592 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Is this sequence equal to A014623 (related to Levine's sequence A011784)?

Compare the definition of e.g.f. A(x) to the trivial statement:

if F(x) = 1 + Series_Reversion( Integral F(-x)^2 dx ) then F(x) = 1/(1-x).

EXAMPLE

E.g.f: A(x) = 1 + x + x^2/2! + 2*x^3/3! + 7*x^4/4! + 33*x^5/5! +...

Let I(x) = Series_Reversion(A(x) - 1) = Integral A(-x) dx then

I(x) = x - x^2/2! + x^3/3! - 2*x^4/4! + 7*x^5/5! - 33*x^6/6! +...

PROG

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

CROSSREFS

Cf. A014623; A144002.

Sequence in context: A059099 A020103 A014623 * A143889 A023053 A058915

Adjacent sequences:  A144002 A144003 A144004 * A144006 A144007 A144008

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Sep 07 2008

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Last modified February 14 09:18 EST 2012. Contains 205614 sequences.