A204049 Number of (n+2)X3 0..3 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..3 introduced in row major order

1379, 10447, 80391, 622031, 4823759, 37451727, 290942303, 2260735279, 17568741535, 136538226767, 1061153916031, 8247213992175, 64097090111007, 498161733185935, 3871710470155071, 30090928730621231, 233866710624036959

Offset

1,1

Comments

Column 1 of A204056

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -31*a(n-2) +69*a(n-3) -176*a(n-4) -8*a(n-5) -116*a(n-6) -132*a(n-7) +240*a(n-8) +144*a(n-9)

Example

Some solutions for n=3
..0..0..0....0..0..0....0..1..0....0..0..0....0..0..0....0..1..0....0..0..0
..0..0..0....1..0..1....2..0..0....0..0..0....0..0..0....0..0..1....0..0..1
..0..0..0....0..1..0....2..0..0....1..0..0....1..0..0....1..0..0....0..0..2
..0..0..0....1..0..1....0..2..1....1..1..0....0..0..0....2..1..0....3..2..0
..1..1..0....1..1..0....2..2..2....2..1..1....0..0..2....0..3..1....2..0..0

Crossrefs

Sequence in context: A260368 A323814 A204056 * A204048 A209791 A051114

Adjacent sequences: A204046 A204047 A204048 * A204050 A204051 A204052

Keyword

nonn

Author

R. H. Hardin Jan 09 2012

Status

approved