A261109 Number of (n+2) X (4+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010001 00010101 or 01010101.

97, 206, 566, 1498, 3908, 10268, 27030, 70980, 186290, 489516, 1286458, 3379154, 8876106, 23319066, 61261972, 160934256, 422777430, 1110660098, 2917747758, 7665011686, 20136272074, 52898777022, 138967021622, 365071414304

Offset

1,1

Comments

Column 4 of A261113.

Links

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

Formula

Empirical: a(n) = a(n-1) +6*a(n-3) +8*a(n-4) +10*a(n-5) +11*a(n-6) +7*a(n-7) +a(n-8) -7*a(n-9) -6*a(n-10) +a(n-11) +3*a(n-12) +a(n-13) for n>14.

Example

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

Crossrefs

Cf. A261113.

Sequence in context: A176011 A157410 A142504 * A142689 A142908 A006310

Adjacent sequences: A261106 A261107 A261108 * A261110 A261111 A261112

Keyword

nonn

Author

R. H. Hardin, Aug 08 2015

Status

approved