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A056417
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Number of step cyclic shifted sequences using exactly four different symbols.
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2
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0, 0, 0, 3, 12, 136, 204, 1437, 3520, 20700, 31956, 317513, 390364, 2973536, 8504720, 32471391, 61276740, 622088400, 790198476, 6798297447, 17290258088, 79394956608, 138325216092, 1460955482487
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OFFSET
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1,4
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COMMENTS
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See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent.
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REFERENCES
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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]
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LINKS
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FORMULA
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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