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.

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

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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)|<>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

A189875 Number of ways to place n nonattacking composite pieces queen + rider[1,5] on an n X n chessboard.

Original entry on oeis.org

1, 0, 0, 2, 10, 0, 0, 0, 40, 52, 152, 260, 1192, 4144, 18408, 71552, 312936, 1498156, 7854672, 44923706, 213840604, 1156549592
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)|<>5k AND |p(j+5k)-p(j)|<>k AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+k<=n, j+5k<=n, m+k<=n

Links

Crossrefs

Cf. A102388, A189873, A189874, A189852

A189859 Number of ways to place n nonattacking composite pieces rook + rider[3,5] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 464, 2274, 13236, 91760, 740562, 5305548, 43237840, 395858894, 4087066620, 46633569480, 509698057110
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)|<>5k AND |p(j+5k)-p(j)|<>3k for all i>=1, j>=1, k>=1, i+3k<=n, j+5k<=n

Links

Crossrefs

Cf. A000170, A189852, A189856

A189861 Number of ways to place n nonattacking composite pieces rook + rider[4,5] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 552, 2826, 17080, 117816, 943250, 7369128, 63533572, 603300392, 6280101222, 71927971040, 836503868762
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+4k)-p(i)|<>5k AND |p(j+5k)-p(j)|<>4k for all i>=1, j>=1, k>=1, i+4k<=n, j+5k<=n

Links

Crossrefs

Cf. A000170, A189852, A189856, A189859
Showing 1-4 of 4 results.

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

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