A274731 Number of 6Xn 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2.

16, 432, 4132, 52912, 687248, 8960464, 116633012, 1520042284, 19800817976, 257995068564, 3361220228816, 43792711784828, 570555977597820, 7433587136161392, 96849404858071388, 1261816522312628012

Offset

1,1

Comments

Row 6 of A274728.

Links

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

Formula

Empirical: a(n) = 15*a(n-1) +a(n-2) -456*a(n-3) +1455*a(n-4) -196*a(n-5) -5263*a(n-6) +5258*a(n-7) +7193*a(n-8) -12179*a(n-9) -1317*a(n-10) +8177*a(n-11) -894*a(n-12) -2235*a(n-13) +104*a(n-14) +350*a(n-15) +27*a(n-16) -44*a(n-17) +5*a(n-18) for n>20

Example

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

Crossrefs

Cf. A274728.

Sequence in context: A359642 A275035 A275140 * A111921 A118994 A223686

Adjacent sequences: A274728 A274729 A274730 * A274732 A274733 A274734

Keyword

nonn

Author

R. H. Hardin, Jul 03 2016

Status

approved