A114561 a(0) = 0; thereafter a(n+1) = 4^a(n).

0, 1, 4, 256, 13407807929942597099574024998205846127479365820592393377723561443721764030073546976801874298166903427690031858186486050853753882811946569946433649006084096

Offset: 0

Author

Jeremy Gardiner, Feb 15 2006

Keywords

• nonn

Comments

Or, define two sequences by q(0) = 0, p(n) = 2^q(n), q(n+1) = p(n)^2; sequence gives q(n).

4-ish analog of A014221 and A014222. - Henry Bottomley, Feb 16 2006

Crossrefs

Cf. A114560, A081651, A014221, A014222.

Programs

Mathematica

NestList[4^# &, 0, 4] (* Paolo Xausa, Jul 23 2024 *)