login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A273876
The successive numbers of digits visible between two odd terms are given by the sequence itself.
0
0, 1, 3, 2, 5, 4, 6, 8, 7, 10, 9, 12, 100, 11, 14, 16, 13, 18, 20, 22, 15, 24, 26, 28, 30, 17, 32, 34, 102, 19, 36, 38, 40, 42, 44, 21, 46, 48, 50, 104, 23, 52, 54, 56, 58, 60, 62, 25, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 1000, 27, 146, 148, 10000, 29
OFFSET
1,3
COMMENTS
The sequence starts with a(1)=0. It is then extended with the smallest integer not yet present and not leading to a contradiction. This sequence is a permutation of the integers >=0.
EXAMPLE
The first two odd terms that appear in the sequence are 1 and 3; between 1 and 3 there are 0 digits and this 0 corresponds to the starting 0 of the sequence.
The next odd term is 5; between 3 and 5 there is 1 digit [which is 2] and this 1 corresponds to the second term of the sequence.
The next odd term is 7; between 5 and 7 there are 3 digits [which are 4, 6 and 8] and this 3 corresponds to the third term of the sequence.
The next odd term is 9; between 7 and 9 there are 2 digits [which are 1 and 0] and this 2 corresponds to the fourth term of the sequence.
The next odd term is 11; between 9 and 11 there are 5 digits [which are 1, 2, 1, 0 and 0] and this 5 corresponds to the fifth term of the sequence. Etc.
CROSSREFS
Sequence in context: A379471 A193231 A191672 * A273865 A286294 A117303
KEYWORD
nonn,base
AUTHOR
Eric Angelini, Jun 02 2016
STATUS
approved