A275127 Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-2) (-1,0) or (-1,1) and new values introduced in order 0..2.

14, 64, 174, 568, 2178, 8321, 31772, 121707, 466252, 1783920, 6825273, 26122839, 99981686, 382636173, 1464403303, 5604594713, 21449747744, 82091326930, 314176968483, 1202409074708, 4601819411125, 17611921823170, 67403757335393

Offset

1,1

Comments

Column 4 of A275131.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -9*a(n-2) +19*a(n-3) -9*a(n-4) -9*a(n-5) +87*a(n-6) -46*a(n-7) -84*a(n-8) +7*a(n-9) -59*a(n-10) -45*a(n-11) +31*a(n-12) +23*a(n-13) +4*a(n-14) -a(n-15) -a(n-16) +a(n-17) for n>20

Example

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

Crossrefs

Cf. A275131.

Sequence in context: A050396 A344597 A069964 * A074354 A212743 A124892

Adjacent sequences: A275124 A275125 A275126 * A275128 A275129 A275130

Keyword

nonn

Author

R. H. Hardin, Jul 17 2016

Status

approved