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A198716
Number of n X n 0..6 arrays with values 0..6 introduced in row major order and no element equal to any horizontal or vertical neighbor
2
1, 4, 2027, 173549032, 601755060211186, 56817439251356046537693
OFFSET
1,2
COMMENTS
Diagonal of A198723
LINKS
Jean-François Alcover, Table of n, a(n) for n = 1..13
EXAMPLE
Some solutions with all values 0 to 6 for n=4
..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1
..2..3..1..0....2..3..1..0....2..3..1..0....2..3..1..0....2..3..1..0
..4..5..2..4....4..0..5..2....0..1..4..3....4..1..0..5....4..2..0..5
..6..0..6..1....6..4..6..0....1..5..3..6....1..6..2..1....3..1..6..1
MATHEMATICA
A198723 = Cases[Import["https://oeis.org/A198723/b198723.txt", "Table"], {_, _}][[All, 2]];
a[n_] := A198723[[2 n^2 - 2 n + 1]];
Table[a[n], {n, 1, 13}] (* Jean-François Alcover, Sep 23 2019 *)
CROSSREFS
Sequence in context: A198975 A160300 A024060 * A365369 A004815 A198907
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 29 2011
STATUS
approved