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 1-5 of 5 results.

A189852 Number of ways to place n nonattacking composite pieces rook + rider[1,5] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 336, 1474, 8340, 57756, 475658, 2812910, 20852460, 181255892, 1817101242, 20435345782, 197871434994
Offset: 1

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Author

Vaclav Kotesovec, Apr 29 2011

Keywords

Comments

a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+k)-p(i)|<>5k AND |p(j+5k)-p(j)|<>k for all i>=1, j>=1, k>=1, i+k<=n, j+5k<=n

Links

Crossrefs

Cf. A000170, A189837, A189850, A189851

A189853 Number of ways to place n nonattacking composite pieces rook + rider[1,6] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 720, 2640, 13596, 87768, 680274, 6090756, 61678252, 482005340, 4454053680, 46705656280, 549750105234
Offset: 1

Views

Author

Vaclav Kotesovec, Apr 29 2011

Keywords

Comments

a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+k)-p(i)|<>6k AND |p(j+6k)-p(j)|<>k for all i>=1, j>=1, k>=1, i+k<=n, j+6k<=n

Links

Crossrefs

Cf. A000170, A189837, A189850, A189851, A189852

A189855 Number of ways to place n nonattacking composite pieces rook + rider[2,4] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 60, 208, 1184, 7840, 36036, 209664, 1395480, 10996728, 83573220, 723835856, 7132494776, 77976981216, 790552134804
Offset: 1

Views

Author

Vaclav Kotesovec, Apr 29 2011

Keywords

Comments

a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+2k)-p(i)|<>4k AND |p(j+4k)-p(j)|<>2k for all i>=1, j>=1, k>=1, i+2k<=n, j+4k<=n

Links

Crossrefs

Cf. A000170, A189851, A189854, A189837

A189874 Number of ways to place n nonattacking composite pieces queen + rider[1,4] on an n X n chessboard.

Original entry on oeis.org

1, 0, 0, 2, 10, 0, 0, 4, 8, 28, 100, 186, 624, 1720, 7288, 30666, 100220, 360208, 1517804, 7302336, 29429672, 139854636, 753288744
Offset: 1

Views

Author

Vaclav Kotesovec, Apr 29 2011

Keywords

Comments

(in fairy chess the rider [1,4] is called a Girafferider)
a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+k)-p(i)|<>4k AND |p(j+4k)-p(j)|<>k AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+k<=n, j+4k<=n, m+k<=n

Links

Crossrefs

Cf. A102388, A189873, A189851

A189858 Number of ways to place n nonattacking composite pieces rook + rider[3,4] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 80, 326, 1566, 9544, 53696, 347382, 2566892, 21907934, 184868860, 1704360992, 17294597926, 192725663600, 2139133978996
Offset: 1

Views

Author

Vaclav Kotesovec, Apr 29 2011

Keywords

Comments

a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+3k)-p(i)|<>4k AND |p(j+4k)-p(j)|<>3k for all i>=1, j>=1, k>=1, i+3k<=n, j+4k<=n.

Links

Crossrefs

Cf. A000170, A189851, A189855.
Showing 1-5 of 5 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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