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A322224 Row sums of triangle A322221. 4
1, 1, 3, 21, 263, 5113, 143323, 5469469, 272621231, 17198531585, 1339483576579, 126230212270629, 14156618029163607, 1863256491324487945, 284412058373417063979, 49835992042915293448749, 9935494230180289986374655, 2236083847858473337146482449, 564194375066091341842030512979, 158608695106487347874486537531701 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
PROG
(PARI) {A322221(n, k) = my(Sx=x, Sy=y, Cx=1, Cy=1); for(i=1, 2*n,
Sx = intformal( Cx*Cy +x*O(x^(2*n)), x);
Cx = 1 + intformal( Sx*Cy, x);
Sy = intformal( Cy*Cx +y*O(y^(2*k)), y);
Cy = 1 + intformal( Sy*Cx, y));
(2*n-2*k)!*(2*k)! *polcoeff(polcoeff(Cx, 2*n-2*k, x), 2*k, y)}
a(n) = sum(k=0, n, A322221(n, k))
for(n=0, 20, print1(a(n), ", "))
CROSSREFS
Cf. A322221.
Sequence in context: A251573 A265002 A012131 * A221094 A098278 A269938
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 01 2019
STATUS
approved

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Last modified February 21 22:50 EST 2024. Contains 370239 sequences. (Running on oeis4.)