A189840 -id:A189840 - cp's OEIS frontend

Showing 1-3 of 3 results.

A189841 Number of ways to place n nonattacking composite pieces rook + rider[5,5] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 672, 4128, 28992, 231936, 2088960, 20017152, 207208704, 2326900992, 28338241536, 373152276480, 5206300028928

Offset: 1

Vaclav Kotesovec, Apr 29 2011

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

V. Kotesovec, Number of ways of placing non-attacking queens, kings, bishops and knights (in English and Czech)
Wikipedia, Fairy chess piece

Cf. A189256, A000170, A189838, A189839, A189840

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

Vaclav Kotesovec, Apr 29 2011

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).

V. Kotesovec, Number of ways of placing non-attacking queens, kings, bishops and knights (in English and Czech)
Wikipedia, Fairy chess piece

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

A189842 Number of ways to place n nonattacking composite pieces rook + rider[6,6] on an n X n chessboard.

Original entry on oeis.org

1, 2, 6, 24, 120, 720, 4800, 34752, 280512, 2528256, 25282560, 278323200, 3242649600, 40330371072, 536528954880, 7633092132864

Offset: 1

Vaclav Kotesovec, Apr 29 2011

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

V. Kotesovec, Number of ways of placing non-attacking queens, kings, bishops and knights (in English and Czech)
Wikipedia, Fairy chess piece

Cf. A189271, A000170, A189838, A189839, A189840, A189841

Showing 1-3 of 3 results.