A381223 Take the list (A381222) of successive values of the smallest number missing from A381019, and keep just the first of any run of successive equal terms.

2, 3, 4, 6, 10, 14, 18, 24, 26, 30, 34, 36, 42, 44, 45, 46, 50, 52, 54, 56, 58, 60, 66, 72, 76, 78, 84, 90, 96, 100, 102, 108, 110, 112, 114, 120, 122, 124, 126, 130, 136, 138, 144, 150, 156, 160, 162, 168, 170, 172, 174, 176, 180, 186, 188, 190, 192

Offset

1,1

Comments

All terms except 2 and 3 are composite numbers, although it is not obvious which composite numbers appear.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..128

Example

A381222 begins 2, 3, 4, 4, 4, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 10, 10, 10, ... and discarding terms which have already been seen we get 2, 3, 4, 6, 10, ...

Crossrefs

Cf. A381019, A381222.

Sequence in context: A229863 A215255 A391137 * A200928 A318558 A347867

Adjacent sequences: A381220 A381221 A381222 * A381224 A381225 A381226

Keyword

nonn

Author

N. J. A. Sloane, Feb 20 2025

Status

approved