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

Author

Vladeta Jovovic, Sep 03 2002

Keywords

• easy
• nonn

Links

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

Crossrefs

Cf. A073701.

Programs

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 *)

Formula

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

Extensions

More terms from Emeric Deutsch, Dec 18 2003

More terms from Harvey P. Dale, Jun 26 2013