A232117 Number of (n+1)X(1+1) 0..2 arrays with every element both >= and <= some horizontal or vertical neighbor

15, 109, 611, 3635, 21717, 129323, 770747, 4593729, 27378111, 163172235, 972498865, 5796045587, 34544152883, 205881488613, 1227043758875, 7313121735911, 43585853505657, 259769588739759, 1548214244035995

Offset

1,1

Comments

Column 1 of A232124

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +4*a(n-2) +12*a(n-3) -7*a(n-4) -14*a(n-5) -33*a(n-6) -22*a(n-7) +4*a(n-8) +4*a(n-9)

Example

Some solutions for n=6
..0..0....0..0....0..0....1..2....0..2....0..0....1..1....1..1....2..1....1..1
..0..2....2..0....0..1....1..2....0..2....1..1....2..2....1..2....2..1....1..1
..1..2....2..0....2..1....1..0....0..0....0..0....2..2....1..2....1..1....2..2
..0..0....2..2....2..1....0..0....2..2....1..0....1..2....0..1....1..2....2..1
..0..2....1..2....2..2....1..0....0..0....1..1....1..1....0..2....1..2....2..0
..0..2....0..1....1..0....2..2....0..0....0..0....0..0....0..2....1..0....2..0
..1..2....0..1....0..0....0..0....1..1....0..0....0..0....1..2....1..0....0..0

Crossrefs

Sequence in context: A365929 A232124 A232204 * A232197 A347500 A205352

Adjacent sequences: A232114 A232115 A232116 * A232118 A232119 A232120

Keyword

nonn

Author

R. H. Hardin, Nov 19 2013

Status

approved