A193485 Number of n X n symmetric 0..6 arrays with each element equal to the product mod 7 of two of its horizontal and vertical neighbors

0, 4, 46, 2731, 700180, 861416011, 4011951942490

Offset

1,2

Links

Table of n, a(n) for n=1..7.

Example

Some solutions for 4X4
..1..6..6..1....0..0..3..4....1..1..1..6....0..0..0..0....4..2..4..2
..6..1..1..6....0..0..6..6....1..6..6..6....0..0..1..1....2..2..4..4
..6..1..6..6....3..6..1..1....1..6..1..1....0..1..1..1....4..4..2..1
..1..6..6..1....4..6..1..1....6..6..1..1....0..1..1..1....2..4..1..1

Crossrefs

Sequence in context: A269005 A107766 A065777 * A006422 A301278 A186677

Adjacent sequences: A193482 A193483 A193484 * A193486 A193487 A193488

Keyword

nonn

Author

R. H. Hardin Jul 27 2011

Status

approved