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A228193 G.f.: exp( Sum_{n>=1} A001850(n^2)*x^n/n ), where A001850 forms the central Delannoy numbers. 1
1, 3, 165, 488007, 63015285321, 313849204040245803, 57549960579131376060801997, 379048169979935686476204047966170767, 88353684521579654155696728418892273040483607185, 721871639878336367921338532273490438662977816273231098545619 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..9.

FORMULA

Logarithmic derivative yields A228192.

EXAMPLE

G.f.: A(x) = 1 + 3*x + 165*x^2 + 488007*x^3 + 63015285321*x^4 +...

where the logarithm of the g.f. begins:

log(A(x)) = 3*x + 321*x^2/2 + 1462563*x^3/3 + 252055236609*x^4/4 +...+ A001850(n^2)*x^n/n +...

PROG

(PARI) {A228192(n)=sum(k=0, n^2, binomial(n^2, k)*binomial(n^2+k, k))}

{a(n)=polcoeff(exp(sum(k=1, n+1, A228192(k)*x^k/k) +x*O(x^n)), n)}

for(n=0, 20, print1(a(n), ", "))

CROSSREFS

Cf. A228192, A001850.

Sequence in context: A185242 A012806 A020545 * A297820 A297990 A298843

Adjacent sequences:  A228190 A228191 A228192 * A228194 A228195 A228196

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Aug 15 2013

STATUS

approved

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Last modified December 6 15:23 EST 2021. Contains 349563 sequences. (Running on oeis4.)