A360415 a(n) is the greatest number k not yet in the sequence such that A065361(n) = A065361(k).

0, 1, 3, 2, 4, 9, 6, 10, 12, 5, 7, 11, 8, 13, 27, 18, 28, 30, 15, 19, 29, 21, 31, 36, 33, 37, 39, 14, 16, 20, 17, 22, 32, 24, 34, 38, 23, 25, 35, 26, 40, 81, 54, 82, 84, 45, 55, 83, 57, 85, 90, 87, 91, 93, 42, 46, 56, 48, 58, 86, 63, 88, 92, 60, 64, 89, 66, 94

Offset: 0

Author

Rémy Sigrist, Feb 06 2023

Keywords

• nonn
• base

Comments

This sequence is a self-inverse permutation of the nonnegative integers.

Examples

			There are four numbers k such that A065361(k) = 8: 14, 15, 18, 27,
- so a(14) = 27,
     a(15) = 18,
     a(18) = 15,
     a(27) = 14.
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..9841
• Rémy Sigrist, PARI program
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

See A360434 for a similar sequence.

Cf. A002487, A005836, A032924, A065361, A360413.

Programs

PARI

See Links section.

Formula

a(A360413(n, k)) = A360413(n, A002487(n) + 1 - k).

a(A032924(n)) = A005836(n+1) for any n > 0.

a(A005836(n+1)) = A032924(n) for any n > 0.