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A260835

Number of (n+2)X(2+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010101.

82, 131, 288, 496, 796, 1645, 2976, 4890, 9332, 17659, 30090, 54846, 104380, 184549, 329454, 618800, 1121728, 1998197, 3692344, 6772932, 12142202, 22172787, 40769872, 73664484, 133728146, 245325455, 445857864, 808254626, 1477620470

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 2 of A260841

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +5*a(n-3) -a(n-4) -3*a(n-5) -5*a(n-6) +3*a(n-9) -2*a(n-10) -5*a(n-11) -2*a(n-12) -a(n-13) +5*a(n-14) -2*a(n-15) -2*a(n-17) +2*a(n-18) for n>19

EXAMPLE

Some solutions for n=4

..1..0..1..0....0..1..1..0....1..0..1..1....0..0..0..0....0..0..0..1

..0..1..0..1....0..0..0..0....0..0..0..0....0..0..0..0....0..0..1..0

..1..0..0..0....0..0..0..0....1..0..0..0....1..0..0..1....0..0..0..0

..0..1..0..0....1..1..0..0....0..0..0..1....0..0..0..1....0..0..0..0

..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..0

..0..0..0..0....0..0..0..0....0..1..0..1....1..1..0..1....1..1..0..0

CROSSREFS

Cf. A260841

Sequence in context: A223088 A039547 A029704 * A173087 A264352 A390678

Adjacent sequences: A260832 A260833 A260834 * A260836 A260837 A260838