A275500 Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,0) or (-1,-1) and new values introduced in order 0..2.

14, 324, 400, 656, 988, 2628, 7140, 19368, 52864, 144228, 394248, 1077956, 2947432, 8062396, 22050256, 60314412, 164976924, 451256880, 1234335036, 3376282048, 9235192524, 25261198432, 69097304872, 189003117812, 516983415672

Offset

1,1

Comments

Column 4 of A275504.

Links

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

Formula

Empirical: a(n) = a(n-1) +8*a(n-2) -28*a(n-4) -9*a(n-5) +55*a(n-6) +16*a(n-7) -70*a(n-8) -9*a(n-9) +56*a(n-10) -28*a(n-12) +a(n-13) +8*a(n-14) -a(n-16) for n>20

Example

Some solutions for n=4
..0..0..0..1. .0..1..1..0. .0..0..1..2. .0..0..1..2. .0..0..1..2
..2..2..1..1. .1..2..0..0. .0..1..2..0. .0..1..2..2. .2..1..2..2
..2..1..1..2. .2..2..0..2. .1..1..2..0. .1..1..2..0. .1..1..2..0
..1..1..0..2. .0..0..1..1. .2..2..0..1. .2..2..0..0. .0..0..0..1

Crossrefs

Cf. A275504.

Sequence in context: A294040 A035018 A264177 * A275397 A275262 A241373

Adjacent sequences: A275497 A275498 A275499 * A275501 A275502 A275503

Keyword

nonn

Author

R. H. Hardin, Jul 30 2016

Status

approved