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A090363 Shifts 1 place left under the BINOMIAL transform of the self-convolution of this sequence. 0
1, 1, 3, 12, 58, 320, 1954, 12961, 92237, 698111, 5583319, 46952892, 413560076, 3803165348, 36419879176, 362366133696, 3738804161990, 39935163833132, 440917642476858, 5025099681646374, 59044001774803872, 714419979588724854 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..21.

FORMULA

G.f.: A(x) = 1 + A(x/(1-x))^2*x/(1-x).

PROG

(PARI) {a(n)=local(A); if(n<0, 0, A=1+x+x*O(x^n); for(k=1, n, B=subst(A^2, x, x/(1-x))/(1-x)+x*O(x^n); A=1+x*B); polcoeff(A, n, x))}

(Maxima) a(n):=if n=0 then 1 else sum(binomial(n-1, k-1)*sum(a(k-1-i)*a(i), i, 0, k-1), k, 1, n); /* Vladimir Kruchinin, Jun 25 2011 */

CROSSREFS

Sequence in context: A038177 A163047 A291488 * A115086 A258173 A196708

Adjacent sequences:  A090360 A090361 A090362 * A090364 A090365 A090366

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Nov 26 2003

STATUS

approved

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Last modified May 17 12:55 EDT 2021. Contains 343971 sequences. (Running on oeis4.)