A056448 - OEIS

A056448

Number of primitive (period n) step cyclic shifted sequence structures using exactly six different symbols.

0, 0, 0, 0, 0, 1, 1, 18, 59, 630, 1681, 28866, 60083, 757576, 3514504, 21423984, 64372109, 1024999170, 2026631203, 26920954613, 105501588414, 742299897060, 1974251382095, 31721456288956, 74052852505684

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OFFSET

1,8

COMMENTS

See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent. Permuting the symbols will not change the structure.

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..25.

FORMULA

A056443(n)-A056442(n).

CROSSREFS

Cf. A056428.

Sequence in context: A048356 A244806 A027055 * A056438 A218617 A105521

Adjacent sequences: A056445 A056446 A056447 * A056449 A056450 A056451

KEYWORD

nonn

AUTHOR

Marks R. Nester

STATUS

approved