A273865 The successive numbers of integers visible between two odd terms are given by the sequence itself.

0, 1, 3, 2, 5, 4, 6, 8, 7, 10, 12, 9, 14, 16, 18, 20, 22, 11, 24, 26, 28, 30, 13, 32, 34, 36, 38, 40, 42, 15, 44, 46, 48, 50, 52, 54, 56, 58, 17, 60, 62, 64, 66, 68, 70, 72, 19, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 21, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 23, 118, 120, 122, 124, 126, 128, 130, 132, 134, 25, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 162, 27, 164, 166, 168, 170, 172, 174, 176, 178, 180, 182, 184, 186, 188, 190, 192, 194, 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. The sequence is a permutation of the integers >=0.

Links

Table of n, a(n) for n=1..113.

Example

The first two odd terms that appear in the sequence are 1 and 3; between 1 and 3 there are 0 integers and this 0 corresponds to the starting 0 of the sequence.
The next odd term is 5 and between 3 and 5 there is 1 integer [which is 2] and this 1 corresponds to the next term of the sequence.
The next odd term is 7 and between 5 and 7 there are 3 integers [which are 4, 6 and 8] and this 3 corresponds to the next term of the sequence.
The next odd term is 9 and between 7 and 9 there are 2 integers [which are 10 and 12] and this 2 corresponds to the next term of the sequence.
The next odd term is 11 and between 9 and 11 there are 5 integers [which are 14, 16, 18, 20 and 22] and this 5 corresponds to the next term of the sequence. Etc.

Crossrefs

Sequence in context: A193231 A191672 A273876 * A286294 A117303 A194904

Adjacent sequences: A273862 A273863 A273864 * A273866 A273867 A273868

Keyword

nonn,base

Author

Eric Angelini, Jun 01 2016

Status

approved