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A288620
Triangle read by rows: T(n,k) = number of step shifted (decimated) sequence structures of length n using exactly k different symbols.
11
1, 1, 1, 1, 2, 1, 1, 5, 4, 1, 1, 5, 8, 3, 1, 1, 19, 50, 37, 9, 1, 1, 13, 54, 63, 26, 4, 1, 1, 47, 284, 479, 299, 83, 11, 1, 1, 51, 525, 1316, 1183, 454, 82, 8, 1, 1, 139, 2370, 8597, 10701, 5761, 1492, 196, 13, 1, 1, 107, 2872, 14619, 24736, 17998, 6429, 1198, 119, 6, 1
OFFSET
1,5
COMMENTS
See A056371 for an explanation of step shifts. 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
EXAMPLE
Triangle begins
1;
1, 1;
1, 2, 1;
1, 5, 4, 1;
1, 5, 8, 3, 1;
1, 19, 50, 37, 9, 1;
1, 13, 54, 63, 26, 4, 1;
1, 47, 284, 479, 299, 83, 11, 1;
1, 51, 525, 1316, 1183, 454, 82, 8, 1;
...
PROG
(PARI) \\ see A056391 for Polya enumeration functions
T(n, k) = NonequivalentStructsExactly(StepShiftPerms(n), k); \\ Andrew Howroyd, Oct 14 2017
CROSSREFS
Columns 2-6 are A056396, A056397, A056398, A056399, A056400.
Row sums are A288621.
Partial row sums include A056391, A056392, A056393, A056394, A056395.
Sequence in context: A076241 A316399 A139347 * A263324 A284949 A263294
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Jun 11 2017
STATUS
approved