A274008 Number of length-n ternary sequences where the sum of each block differs by at most 1 from every other block of the same length.

1, 3, 7, 15, 27, 47, 71, 107, 151, 207, 271, 355, 447, 563, 691, 835, 995, 1187, 1391, 1631, 1887, 2167, 2467, 2811, 3171, 3571, 3995, 4455, 4939, 5479, 6035, 6651, 7299, 7987, 8707, 9475, 10267, 11131, 12031, 12979, 13959, 15019, 16103, 17271, 18479, 19735

Offset

0,2

Links

Table of n, a(n) for n=0..45.

Formula

a(n) = 2*A005598(n) - 1. - Rémy Sigrist, Oct 11 2022

Example

For n = 2 the only strings omitted are 02 and 20.

Crossrefs

Cf. A005598, which is the analogous sequence where "ternary" is replaced by "binary".

Cf. A274005, which is the analogous sequence where "ternary" is replaced by "binary" and "1" is replaced by "2".

Sequence in context: A182836 A360452 A097080 * A146742 A146425 A147595

Adjacent sequences: A274005 A274006 A274007 * A274009 A274010 A274011

Keyword

nonn

Author

Jeffrey Shallit, Jun 06 2016

Extensions

More terms from Rémy Sigrist, Oct 11 2022

Status

approved