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A210028 E.g.f. A(x) satisfies: A(x) = 1 / [Sum_{n>=0} (-x)^n*A(x)^n/n!^2], where A(x) = Sum_{n>=0} a(n)*x^n/n!^2. 0
1, 1, 7, 136, 5243, 337926, 32835687, 4489157296, 821988647139, 194271151505410, 57588227767731323, 20926176288185481600, 9148417925040487304917, 4737353391259130086721836, 2867750643606307859579827455, 2006632021748934960936683256384 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..15.

EXAMPLE

E.g.f.: A(x) = 1 + x + 7*x^2/2!^2 + 136*x^3/3!^2 + 5243*x^4/4!^2 + 337926*x^5/5!^2 +...

such that

A(x) = 1/(1 - x*A(x) + x^2*A(x)^2/2!^2 - x^3*A(x)^3/3!^2 + x^4*A(x)^4/4!^2  +...).

PROG

(PARI) {a(n)=n!^2*polcoeff(1/x*serreverse(x*sum(m=0, n, (-x)^m/m!^2)+x^2*O(x^n)), n)}

for(n=0, 31, print1(a(n), ", "))

CROSSREFS

Sequence in context: A292395 A081793 A296595 * A243684 A260535 A220380

Adjacent sequences:  A210025 A210026 A210027 * A210029 A210030 A210031

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 16 2012

STATUS

approved

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Last modified November 30 04:44 EST 2021. Contains 349418 sequences. (Running on oeis4.)