A238980 Underline all odd digits of the sequence. The sequence gives the successive lengths of the underlined/not underlined blocks of digits.

1, 2, 4, 3, 5, 7, 9, 6, 8, 21, 11, 13, 20, 22, 24, 23, 15, 17, 19, 31, 26, 28, 40, 33, 35, 37, 39, 42, 44, 46, 48, 60, 62, 64, 66, 68, 80, 25, 51, 53, 55, 57, 59, 82, 84, 86, 88, 200, 201, 71, 73, 75, 77, 79, 91, 93, 95, 97, 10, 202, 204, 206, 208, 220, 222, 224, 99, 111, 113, 115, 117, 119, 131, 133, 12, 226, 228, 240, 242, 244, 246, 248, 27, 135, 137, 139, 151, 110, 260, 262, 264, 266, 268, 29, 153, 155, 157, 159, 171, 173, 280, 282, 284, 286, 288, 400, 402, 404, 406, 408, 41, 175, 177, 179, 191, 193, 195, 197, 199, 14

Offset

1,2

Comments

A self-describing sequence. The sequence is always extended with the smallest unused integer not leading to a contradiction.

Links

Table of n, a(n) for n=1..120.

Example

(1)(2,4)(3,5,7,9)(6,8,2)(1,11,13)(20,22,24,2)(3,15,17,19,31)... are the first blocks of underlined/not underlined digits; the successive lengths are 1, 2, 4, 3, 5, 7, 9, ... which is the sequence itself.

Crossrefs

Sequence in context: A374800 A093506 A307485 * A327143 A343313 A082006

Adjacent sequences: A238977 A238978 A238979 * A238981 A238982 A238983

Keyword

nonn,base

Author

Eric Angelini, Mar 07 2014; corrected Jun 22 2015

Status

approved