A276244 Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-1,1) or (0,-2) and new values introduced in order 0..2.

6, 72, 279, 1447, 7316, 36744, 188696, 966555, 4951790, 25428687, 130544436, 670268288, 3442454805, 17679508687, 90799294877, 466351655607, 2395200182414, 12301874919271, 63183522824553, 324515866624876, 1666740802461017

Offset

1,1

Comments

Column 4 of A276248.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -5*a(n-2) +52*a(n-3) -290*a(n-4) +186*a(n-5) -750*a(n-6) +4724*a(n-7) -3230*a(n-8) +4486*a(n-9) -32737*a(n-10) +27394*a(n-11) -16656*a(n-12) +107909*a(n-13) -100918*a(n-14) +41478*a(n-15) -188601*a(n-16) +184276*a(n-17) -63820*a(n-18) +185119*a(n-19) -179543*a(n-20) +55691*a(n-21) -102915*a(n-22) +95614*a(n-23) -26448*a(n-24) +31475*a(n-25) -27524*a(n-26) +6584*a(n-27) -4916*a(n-28) +4089*a(n-29) -840*a(n-30) +341*a(n-31) -278*a(n-32) +50*a(n-33) -7*a(n-34) +6*a(n-35) -a(n-36) for n>37

Example

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

Crossrefs

Cf. A276248.

Sequence in context: A250071 A192990 A379393 * A361571 A282817 A274955

Adjacent sequences: A276241 A276242 A276243 * A276245 A276246 A276247

Keyword

nonn

Author

R. H. Hardin, Aug 25 2016

Status

approved