A357986 a(n) is the unique k such that A357579(k) = A007916(n), or -1 if no such k exists.

1, 2, 4, 5, 3, 7, 8, 6, 12, 14, 11, 9, 10, 16, 13, 20, 19, 15, 25, 18, 17, 21, 27, 26, 22, 29, 23, 24, 28, 31, 32, 30, 36, 34, 33, 38, 35, 43, 41, 44, 37, 46, 40, 39, 49, 51, 42, 48, 45, 50, 47, 55, 57, 54, 52, 53, 63, 58, 56, 67, 60, 59, 62, 65, 61, 69, 66

Offset: 1

Author

Rémy Sigrist, Oct 23 2022

Keywords

• nonn

Examples

			A357579(36) = 42 = A007916(33), so a(33) = 36.
		

Links

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

Crossrefs

Cf. A007916, A357579.

Programs

PARI

See Links section.