|
|
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
|
|
|
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
|
|
|
KEYWORD
|
nonn,changed
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|