A379691 Expansion of e.g.f. (1/x) * Series_Reversion( x * exp(-x) * (1 - x*exp(2*x)) ).

1, 2, 17, 274, 6597, 212736, 8624581, 421843472, 24185705417, 1591194859264, 118184516071641, 9782950785024000, 893132377427288653, 89156432069922504704, 9661304014254414999821, 1129505503357457643206656, 141711496280128816909982097, 18992404410135723679211716608

Offset

0,2

Links

Table of n, a(n) for n=0..17.

Formula

a(n) = (1/(n+1)) * Sum_{k=0..n} (3*n-2*k+1)^k * (2*n-k)!/(k! * (n-k)!).

Prog

(PARI) a(n) = sum(k=0, n, (3*n-2*k+1)^k * (2*n-k)!/(k!*(n-k)!))/(n+1);

Crossrefs

Cf. A379661, A379689, A379690.

Sequence in context: A176585 A086534 A198287 * A338635 A268705 A380771

Adjacent sequences: A379688 A379689 A379690 * A379692 A379693 A379694

Keyword

nonn

Author

Seiichi Manyama, Dec 29 2024

Status

approved