A318012 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

8, 97, 508, 3062, 17703, 103633, 603215, 3512154, 20446744, 119050218, 693180972, 4036155290, 23501168666, 136839336291, 796768793476, 4639312324422, 27013128767994, 157288207910023, 915835429361804, 5332596422248712

Offset

1,1

Comments

Column 4 of A318016.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +10*a(n-2) -30*a(n-3) -17*a(n-4) +84*a(n-5) +19*a(n-6) +24*a(n-7) +14*a(n-8) -490*a(n-9) -213*a(n-10) +715*a(n-11) +303*a(n-12) -544*a(n-13) -269*a(n-14) -82*a(n-15) -439*a(n-16) +318*a(n-17) +647*a(n-18) +21*a(n-19) -71*a(n-20) -24*a(n-21) -90*a(n-22) -21*a(n-23) +20*a(n-24) +4*a(n-25) -a(n-26) for n>29

Example

Some solutions for n=5
..0..0..1..1. .0..1..0..1. .0..1..1..0. .0..1..1..0. .0..1..1..1
..0..1..1..0. .1..0..0..0. .0..0..0..1. .0..1..1..0. .0..1..1..1
..1..1..0..0. .1..0..0..1. .0..0..1..1. .0..1..1..1. .0..1..1..1
..1..1..0..0. .1..1..1..1. .0..0..1..1. .0..1..1..1. .0..0..0..0
..1..0..0..1. .1..0..0..1. .1..0..1..1. .0..0..1..0. .0..0..1..1

Crossrefs

Cf. A318016.

Sequence in context: A317005 A002506 A367352 * A320398 A218451 A262777

Adjacent sequences: A318009 A318010 A318011 * A318013 A318014 A318015

Keyword

nonn

Author

R. H. Hardin, Aug 12 2018

Status

approved