A056415 Number of step cyclic shifted sequences using exactly two different symbols.

0, 1, 2, 4, 4, 11, 8, 22, 20, 43, 28, 156, 72, 243, 366, 691, 520, 2635, 1608, 7384, 8866, 19399, 16768, 94482, 67560, 216273, 277532, 815556, 662368, 4500265, 2311468, 8466187, 13045106, 31593283, 40937604, 159772174, 103197488, 401913695

Offset

1,3

Comments

See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent.

References

M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]

Links

Table of n, a(n) for n=1..38.

Formula

a(n) = A002729(n) - 2.

Crossrefs

Cf. A002729.

Sequence in context: A202076 A199825 A121049 * A242993 A366045 A263382

Adjacent sequences: A056412 A056413 A056414 * A056416 A056417 A056418

Keyword

nonn

Author

Marks R. Nester

Extensions

Added more terms (from A002729), Joerg Arndt, Aug 27 2014

Status

approved