A260539 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010001.

193, 310, 774, 1411, 2226, 5592, 11370, 18899, 40776, 88106, 155906, 309795, 670458, 1259060, 2411996, 5101845, 9988886, 18999278, 39063112, 78266591, 150050760, 301477144, 608976908, 1182523707, 2342361446, 4726202066, 9284557350

Offset

1,1

Comments

Column 3 of A260544.

Links

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

Formula

Empirical: a(n) = 6*a(n-3) +6*a(n-4) +a(n-5) -5*a(n-6) -9*a(n-7) -13*a(n-8) +7*a(n-9) +10*a(n-10) -3*a(n-11) +3*a(n-12) -10*a(n-13) -16*a(n-14) -14*a(n-15) -3*a(n-16) -2*a(n-17) -a(n-18) +4*a(n-19) for n>22.

Example

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

Crossrefs

Cf. A260544.

Sequence in context: A146360 A050964 A015988 * A142743 A014755 A238667

Adjacent sequences: A260536 A260537 A260538 * A260540 A260541 A260542

Keyword

nonn

Author

R. H. Hardin, Jul 28 2015

Status

approved