A297696 Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 4 neighboring 1s.

8, 19, 95, 293, 1244, 4277, 16931, 61040, 234262, 862457, 3264643, 12131248, 45639021, 170292842, 638909917, 2388332666, 8949721529, 33482510155, 125400009557, 469313539433, 1757268204363, 6577689516815, 24626450519312

Offset

1,1

Comments

Row 3 of A297694.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +10*a(n-2) -24*a(n-3) -24*a(n-4) +43*a(n-5) +22*a(n-6) -17*a(n-7) -4*a(n-8) +2*a(n-9)

Example

Some solutions for n=7
..1..1..0..1..0..0..0. .1..0..0..0..0..0..0. .1..1..1..1..1..1..1
..0..1..1..1..1..0..1. .1..0..0..0..1..0..0. .0..1..0..1..0..1..0
..0..0..0..0..0..0..0. .1..0..0..1..1..1..0. .1..1..1..1..1..1..1

Crossrefs

Cf. A297694.

Sequence in context: A091560 A061877 A297459 * A242188 A119284 A177124

Adjacent sequences: A297693 A297694 A297695 * A297697 A297698 A297699

Keyword

nonn

Author

R. H. Hardin, Jan 03 2018

Status

approved