A266010 Number of nX6 integer arrays with each element equal to the number of horizontal and antidiagonal neighbors equal to itself.

2, 1, 18, 61, 154, 473, 1561, 4909, 15560, 49716, 158446, 505111, 1610417, 5134905, 16372772, 52204960, 166458078, 530758391, 1692351797, 5396146261, 17205878204, 54861813048, 174929641642, 557771939947, 1778483829141, 5670785032981

Offset

1,1

Comments

Column 6 of A266012.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +6*a(n-3) -4*a(n-4) -14*a(n-5) -29*a(n-6) +2*a(n-7) -a(n-8) +36*a(n-9) -20*a(n-10) -16*a(n-11) +4*a(n-12) +84*a(n-13) +60*a(n-14) +96*a(n-15) -16*a(n-16) +16*a(n-17) +48*a(n-18) +64*a(n-19) for n>21

Example

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

Crossrefs

Cf. A266012.

Sequence in context: A089014 A063426 A316195 * A349960 A181870 A070890

Adjacent sequences: A266007 A266008 A266009 * A266011 A266012 A266013

Keyword

nonn

Author

R. H. Hardin, Dec 20 2015

Status

approved