A281900 Index of first occurrence of n in A281579, or -1 if n does not appear there..

1, 3, 6, 7, 15, 16, 34, 240, 241, 317, 502, 503, 504, 505, 1077, 1178, 1179, 1806, 4866, 4901, 4902, 4946, 4947, 8195, 8196, 8197, 8198, 8199, 8200, 8201, 8202, 8203, 8204, 45393, 45485, 45486, 96358, 96359, 96360, 96361, 96362, 96363, 96364, 96365, 96366

Offset: 2

Author

Rémy Sigrist, Feb 01 2017

Keywords

• nonn

Comments

The sequence is strictly increasing.

It is conjectured that every number >= 2 does appear in A281579.

a(n) is also the index of the first occurrence of n-1 in A380317, or -1 if n-1 does not appear there.

Links

• Rémy Sigrist, Table of n, a(n) for n = 2..1904 (a(2)-a(968) added on Feb 01 2017, a(969)-a(1904) added on Feb 06 2017)
• Rémy Sigrist, C++ program for A281900

Crossrefs

Cf. A281579, A310387.

Extensions

Escape clause added to definition by N. J. A. Sloane, Feb 17 2025