A355405 Inverse permutation to A269838.

1, 2, 3, 4, 5, 6, 9, 8, 7, 10, 17, 11, 33, 18, 13, 12, 65, 14, 129, 20, 19, 34, 257, 16, 21, 66, 15, 25, 513, 22, 1025, 24, 35, 130, 37, 23, 2049, 258, 67, 26, 4097, 38, 8193, 36, 29, 514, 16385, 27, 41, 42, 131, 68, 32769, 30, 49, 40, 259, 1026

Offset: 1

Author

Rémy Sigrist, Jul 01 2022

Keywords

• nonn

Examples

			A269838(38) = 42, so a(42) = 38.
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• Rémy Sigrist, PARI program
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A269838.

Programs

PARI

See Links section.

Formula

a(prime(n)) = 2^(n-1) + 1 (where prime(n) denotes the n-th prime number).