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

Author

R. H. Hardin, Aug 25 2016

Keywords

• nonn

Comments

Column 4 of A276248.

Examples

			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
		

Links

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

Crossrefs

Cf. A276248.

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