A203882 Number of (n+1) X 4 0..6 arrays with every 2 X 2 subblock having equal diagonal elements or equal antidiagonal elements.

107653, 7501753, 543848893, 39572771665, 2880436707253, 209668438383145, 15261911634884845, 1110925438997643073, 80865057189988449637, 5886225355184724720793, 428462554060882790003485

Offset

1,1

Comments

Column 3 of A203887.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 79*a(n-1) -450*a(n-2) -144*a(n-3).

Empirical g.f.: 49*x*(2197 - 20466*x - 7056*x^2) / (1 - 79*x + 450*x^2 + 144*x^3). - Colin Barker, Jun 05 2018

Example

Some solutions for n=4:
..2..1..1..2....1..0..1..4....0..3..1..5....4..3..2..6....1..2..6..6
..0..2..1..1....0..1..3..1....5..0..3..1....5..4..3..2....1..1..2..6
..0..0..2..1....1..4..1..6....3..5..0..3....6..5..4..3....1..5..1..2
..5..0..0..2....0..1..0..1....5..5..5..0....1..6..5..4....0..1..1..1
..4..5..0..0....1..3..1..6....2..5..4..5....4..1..6..5....0..0..1..3

Crossrefs

Cf. A203887.

Sequence in context: A158964 A248446 A202404 * A178284 A157825 A205607

Adjacent sequences: A203879 A203880 A203881 * A203883 A203884 A203885

Keyword

nonn

Author

R. H. Hardin, Jan 07 2012

Status

approved