A198975 Number of n X n 0..5 arrays with values 0..5 introduced in row major order and no element equal to any horizontal or vertical neighbor.

1, 4, 1835, 53082012, 30525244435834, 310387893630465965693, 55676868201599759013090066735

Offset: 1

Author

R. H. Hardin Nov 01 2011

Keywords

• nonn

Comments

Diagonal of A198982

Examples

			Some solutions with all values from 0 to 5 for n=4
..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1
..1..2..3..0....1..0..2..0....1..2..3..0....1..0..2..0....1..0..2..0
..4..3..2..3....0..3..4..3....4..3..2..5....0..2..1..3....3..4..5..2
..2..1..5..2....5..2..1..2....1..4..1..4....4..3..5..0....4..2..3..5
		

Links

• Jean-François Alcover, Table of n, a(n) for n = 1..13

Programs

Mathematica

A198982 = Cases[Import["https://oeis.org/A198982/b198982.txt", "Table"], {, }][[All, 2]];
a[n_] := A198982[[2 n^2 - 2 n + 1]];
Table[a[n], {n, 1, 13}] (* Jean-François Alcover, Sep 23 2019 *)