A338347 a(n) = index k such that A338338(k) = n, or -1 if n does not appear in A338338.

1, 2, 5, 3, 7, 4, 11, 10, 6, 8, 19, 14, 33, 12, 15, 18, 38, 22, 42, 9, 23, 20, 54, 26, 68, 32, 27, 13, 73, 16, 78, 37, 28, 39, 60, 35, 82, 41, 34, 17, 91, 24, 95, 21, 44, 53, 120, 36, 90, 31, 49, 64, 125, 56, 29, 25, 43, 72, 145, 45, 152, 79, 48, 81, 69, 57, 157, 40, 55, 46

Offset: 1

Author

N. J. A. Sloane, Oct 27 2020

Keywords

• nonn

Comments

There is a strong conjecture that A338338 is a permutation of the positive integers. If that is true, this is the inverse permutation.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• Rémy Sigrist, PARI program for A338347

Crossrefs

Cf. A338338-A338349.

Programs

PARI

See Links section.