A260229 a(n) = floor(e^(n!)).

2, 7, 403, 26489122129, 13041808783936322797338790280986488113446079415755132

Offset

1,1

Comments

The exponential growth in the number of permutations of n elements.

Next term is too big to be included.

Links

Table of n, a(n) for n=1..5.

Formula

a(n) = A000149(A000142(n)).

a(n) = floor(sqrt(e^A052849(n) - e^A000142(n) + sqrt(e^A052849(n) - e^A000142(n) + sqrt(e^A052849(n) - e^A000142(n) + ...)))).

Example

a(1) = floor(e^(1!)) = floor(e) = 2.

Mathematica

Table[Floor[E^n!], {n, 1, 7}]

Prog

(PARI) default(realprecision, 100); vector(5, n, floor(exp(n!))) \\ Michel Marcus, Aug 06 2015

Crossrefs

Cf. A000149, A000142.

Cf. A050923, A100731.

Sequence in context: A176748 A262088 A110386 * A321134 A027732 A073698

Adjacent sequences: A260226 A260227 A260228 * A260230 A260231 A260232

Keyword

nonn

Author

Ilya Gutkovskiy, Jul 20 2015

Status

approved