A074702 a(n) = ((n+1)^2*(n-1)*a(n-1)+(-1)^(n+1))/n.

1, 4, 43, 806, 23213, 947864, 51997111, 3685295242, 327581799289, 35673657942572, 4670006130663971, 723461783075360174, 130890931830249779173, 27346855400248614577216, 6534075316966068976316143, 1770326031190494313270654994, 539845302687736618823239734641

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..252

Formula

a(n) = round((n+1)!^2*BesselJ(0, 2))/n.

Mathematica

nxt[{n_, a_}]:={n+1, (n*a*(n+2)^2+(-1)^(n+2))/(n+1)}; Transpose[ NestList[ nxt, {1, 1}, 15]][[2]] (* Harvey P. Dale, Jun 26 2013 *)

Crossrefs

Cf. A073701.

Sequence in context: A198205 A277639 A326432 * A197717 A277456 A317140

Adjacent sequences: A074699 A074700 A074701 * A074703 A074704 A074705

Keyword

easy,nonn

Author

Vladeta Jovovic, Sep 03 2002

Extensions

More terms from Emeric Deutsch, Dec 18 2003

More terms from Harvey P. Dale, Jun 26 2013

Status

approved