A260604 Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000101 00010001 or 00010101

125, 250, 610, 1334, 3343, 7516, 19069, 42696, 108592, 244492, 620922, 1394188, 3543940, 7964144, 20236020, 45470332, 115549194, 259609220, 659718394, 1482402604, 3766971094, 8463829616, 21508165126, 48327274404, 122806995718

Offset

1,1

Comments

Column 3 of A260609

Links

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

Formula

Empirical: a(n) = 3*a(n-2) +14*a(n-4) +9*a(n-6) -25*a(n-8) +136*a(n-10) -65*a(n-12) -59*a(n-14) +111*a(n-16) -55*a(n-18) +22*a(n-20) -32*a(n-22) +18*a(n-24) for n>29

Example

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

Crossrefs

Cf. A260609

Sequence in context: A031473 A045214 A045199 * A023079 A172460 A338469

Adjacent sequences: A260601 A260602 A260603 * A260605 A260606 A260607

Keyword

nonn

Author

R. H. Hardin, Jul 29 2015

Status

approved