A356516 a(n) is the least k such that A356515(k) = n.

0, 1, 3, 31, 9007199254740991

Offset

0,3

Comments

All terms belong to A000225.

a(5) = 2^1235346792567893 - 1 is too large to fit in the data section or in a b-file.

Links

Table of n, a(n) for n=0..4.

Formula

a(n) = A356517(2, A356517(3, ... A356517(n, n) ...)) for n > 1.

Example

For n = 4:
- A356517(4, 4) = 7,
- A356517(3, 7) = 53,
- A356517(2, 53) = 9007199254740991,
- so a(4) = 9007199254740991.

Prog

(PARI) A356517(n, k) = { (1+k%(n-1))*n^(k\(n-1))-1 }
a(n) = { my (v=n); forstep (b=n, 2, -1, v=A356517(b, v)); v }

Crossrefs

Cf. A000225, A356515, A356517.

Sequence in context: A367038 A317482 A136582 * A173649 A210648 A119937

Adjacent sequences: A356513 A356514 A356515 * A356517 A356518 A356519

Keyword

nonn,base,bref

Author

Rémy Sigrist, Aug 10 2022

Status

approved