cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A288620 Triangle read by rows: T(n,k) = number of step shifted (decimated) sequence structures of length n using exactly k different symbols.

Original entry on oeis.org

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

Views

Author

Andrew Howroyd, Jun 11 2017

Keywords

Comments

See A056371 for an explanation of step shifts. Permuting the symbols will not change the structure.

Examples

			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;
...
		

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]

Crossrefs

Columns 2-6 are A056396, A056397, A056398, A056399, A056400.
Row sums are A288621.
Partial row sums include A056391, A056392, A056393, A056394, A056395.

Programs

  • PARI
    \\ see A056391 for Polya enumeration functions
    T(n,k) = NonequivalentStructsExactly(StepShiftPerms(n), k); \\ Andrew Howroyd, Oct 14 2017

A056402 Number of primitive (aperiodic) step shifted (decimated) sequence structures using a maximum of three different symbols.

Original entry on oeis.org

1, 1, 3, 8, 13, 65, 67, 322, 573, 2495, 2979, 23294, 22217, 133081, 300947, 909050, 1345633, 10766559, 10762819, 72954582, 145362861, 523026545, 713213955, 5893685746, 7060765719, 35303760331
Offset: 1

Views

Author

Keywords

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]

Crossrefs

Cf. A056382.

Formula

Sum mu(d)*A056392(n/d) where d|n.

A056397 Number of step shifted (decimated) sequence structures using exactly three different symbols.

Original entry on oeis.org

0, 0, 1, 4, 8, 50, 54, 284, 525, 2370, 2872, 22748, 21866, 131750, 298792, 904918, 1341518, 10745090, 10748218, 72889084, 145274556, 522819590, 713023210, 5892634240, 7059926605, 35300985550, 70604008204
Offset: 1

Views

Author

Keywords

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]

Crossrefs

Column 3 of A288620.
Cf. A056377.

Formula

A056398 Number of step shifted (decimated) sequence structures using exactly four different symbols.

Original entry on oeis.org

0, 0, 0, 1, 3, 37, 63, 479, 1316, 8597, 14619, 155999, 211231, 1732907, 5302823, 21559909, 43398413, 466495335, 625545865, 5659500031, 15126813765, 72778025365, 132561145173, 1460519554091, 2338565021382
Offset: 1

Views

Author

Keywords

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]

Crossrefs

Column 4 of A288620.
Cf. A056378.

Formula

Showing 1-4 of 4 results.