A194890 Number of lower triangles of an n X n 0..5 array with new values introduced in row major order 0..5 and no two horizontal or vertical neighbors of any element equal

1, 3, 34, 3936, 1797696, 2054111040, 5741390328960, 39210440893622016

Offset

1,2

Comments

Column 5 of A194893

Links

Table of n, a(n) for n=1..8.

Example

Some solutions for 4X4
..0........0........0........0........0........0........0........0
..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2
..1.3.4....3.4.1....1.3.4....3.2.1....3.3.4....3.2.1....3.0.1....3.3.4
..0.0.4.1..5.5.2.0..2.3.5.2..0.0.1.2..0.1.1.0..3.4.5.0..3.4.4.3..2.1.0.5

Crossrefs

Sequence in context: A366137 A337069 A102104 * A197434 A194891 A194892

Adjacent sequences: A194887 A194888 A194889 * A194891 A194892 A194893

Keyword

nonn

Author

R. H. Hardin Sep 04 2011

Status

approved