A056072 a(n) = floor(e^e^ ... ^e), with n e's.

1, 2, 15, 3814279

Offset: 0

Author

Robert G. Wilson v, Jul 26 2000

Keywords

• nonn

Comments

The next term is too large to include.

From Vladimir Reshetnikov, Apr 27 2013: (Start)

a(4) = 2331504399007195462289689911...2579139884667434294745087021 (1656521 decimal digits in total), given by initial segment of A085667.

a(5) has more than 10^10^6 decimal digits.

a(6) has more than 10^10^10^6 decimal digits. (End)

Crossrefs

Cf. A001113, A004002, A003417, A064107, A159825, A073226, A073227, A085667, A096232, A225064, A225053.

Programs

Maple

p:= n-> `if`(n=0, 1, exp(1)^p(n-1)):
a:= n-> floor(p(n)):
seq(a(n), n=0..3);  # Alois P. Heinz, Jul 20 2024

Mathematica

Floor[NestList[Exp, 1, 3]] (* Vladimir Reshetnikov, Apr 29 2013 *)

PARI

A056072(n,f=floor)=f(exp(if(n>0,A056072(n-1,x->x))))  \\ M. F. Hasler, May 01 2013