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A056420
Number of primitive (period n) step cyclic shifted sequences using a maximum of three different symbols.
2
3, 3, 7, 15, 21, 79, 75, 306, 433, 1605, 1695, 12662, 10461, 57759, 122791, 347895, 476049, 3596917, 3401967, 22005312, 41597289, 142675887, 186077883, 1476684552, 1694657979, 8147271993, 15690973311
OFFSET
1,1
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]
FORMULA
Sum mu(d)*A056411(n/d) where d|n.
CROSSREFS
Sequence in context: A218242 A218288 A356976 * A030069 A004043 A104176
KEYWORD
nonn
STATUS
approved