A275375 The odd digits in the sequence appear in blocks and the successive sizes of these blocks are given by the sequence itself.

1, 2, 3, 5, 4, 6, 7, 9, 10, 8, 11, 13, 12, 15, 17, 20, 19, 31, 33, 21, 35, 37, 39, 22, 23, 51, 53, 55, 57, 24, 25, 59, 71, 73, 75, 14, 26, 27, 77, 79, 91, 16, 28, 29, 93, 95, 97, 99, 110, 40, 41, 111, 113, 115, 117, 42, 43, 119, 131, 133, 112, 44, 45, 135, 137, 139, 151, 114, 46, 47, 153, 155, 157, 159, 171, 18, 48, 49, 173, 175, 177, 179, 191

Offset

1,2

Comments

This is the lexicographically first such sequence starting with a(1)=1 and being always extended with the smallest integer not yet present that doesn't lead to a contradiction.

Links

Eric Angelini, Table of n, a(n) for n = 1..1002

Example

The blocks of odd digits are indicated here by parentheses; the successive block-sizes are 1, 2, 3, 5, 4, 6, 7,... which reproduces the sequence itself:
(1),2,(3,5),4,6,(7,9,1)0,8,(11,13,1)2,(15,17),20,(19,31,33),2(1,35,37,39),22,...

Crossrefs

Cf. A275375.

Sequence in context: A105363 A279337 A279336 * A225047 A279338 A279348

Adjacent sequences: A275372 A275373 A275374 * A275376 A275377 A275378

Keyword

base,nonn

Author

Eric Angelini and Jean-Marc Falcoz, Jul 25 2016

Status

approved