A135487 a(n) = (n^2+5*n+5)*(2*n+2)!/(n+4)!.

19, 232, 3690, 72600, 1705704, 46650240, 1456902720, 51181804800, 1998434592000, 85878536325120, 4028521809312000, 204866151025536000, 11227636547487360000, 659746302934118400000, 41380369671344191488000, 2759500311807527608320000

Offset

2,1

Links

G. C. Greubel, Table of n, a(n) for n = 2..250

V. I. Arnold, Smooth function statistics, Funct. Anal. Other. Math., 1 (2006), 111-118.

Index entries for doubling substrings

Mathematica

Table[(n^2 + 5*n + 5)*(2*n + 2)!/(n + 4)!, {n, 2, 25}] (* G. C. Greubel, Oct 15 2016 *)

Crossrefs

Cf. A120420.

Sequence in context: A125431 A104116 A028026 * A025965 A276201 A025960

Adjacent sequences: A135484 A135485 A135486 * A135488 A135489 A135490

Keyword

nonn

Author

N. J. A. Sloane, Feb 21 2008

Status

approved