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.

A189844 Number of ways to place n nonattacking composite pieces rook + semi-rider[3,3] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 22, 98, 534, 3334, 23724, 191820, 1704532, 16689868, 179288892, 2069311996, 25760882744, 345073745880, 4900331447624
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(j+3k)-p(j)<>3k for all j>=1, k>=1, j+3k<=n.
For information about semi-pieces see semi-bishop (A187235) and semi-queen (A099152).

Links

Crossrefs

Cf. A189282, A099152, A189843, A189839, A187235

A189846 Number of ways to place n nonattacking composite pieces rook + semi-rider[4,4] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 114, 628, 4062, 30360, 251658, 2308648, 23351268, 259031232, 3091784268, 39697601392, 546982720164, 8064677125440
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(j+4k)-p(j)<>4k for all j>=1, k>=1, j+4k<=n
For information about semi-pieces see semi-bishop (A187235) and semi-queen (A099152).

Links

Crossrefs

Cf. A189283, A099152, A189843, A189844, A189840, A187235

A189847 Number of ways to place n nonattacking composite pieces rook + semi-rider[5,5] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 696, 4572, 34260, 290328, 2751480, 28426056, 318900264, 3874868280, 50813711808, 716309557440, 10721493269568
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(j+5k)-p(j)<>5k for all j>=1, k>=1, j+5k<=n
For information about semi-pieces see semi-bishop (A187235) and semi-queen (A099152).

Links

Crossrefs

Cf. A189284, A099152, A189843, A189844, A189846, A189841, A187235

A189848 Number of ways to place n nonattacking composite pieces rook + semi-rider[6,6] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 720, 4920, 37488, 319644, 3033264, 31784280, 364902480, 4509620040, 59768680032, 847746532152
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(j+6k)-p(j)<>6k for all j>=1, k>=1, j+6k<=n
For information about semi-pieces see semi-bishop (A187235) and semi-queen (A099152).

Links

Crossrefs

Cf. A189285, A099152, A189843, A189844, A189846, A189847, A189842, A187235
Showing 1-4 of 4 results.

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

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