A202371 Number of (n+2)X3 binary arrays avoiding patterns 001 and 111 in rows and columns

98, 257, 611, 1326, 2815, 5718, 11362, 22164, 42507, 80633, 151352, 281811, 521224, 958418, 1754004, 3196693, 5805401, 10510754, 18978585, 34187852, 61457038, 110271668, 197530737, 353309613, 631087988, 1125880395, 2006365746

Offset

1,1

Comments

Column 1 of A202378

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) -2*a(n-3) -12*a(n-4) -a(n-5) +12*a(n-6) +15*a(n-7) -2*a(n-8) -8*a(n-9) -13*a(n-10) -5*a(n-11) +a(n-12) +8*a(n-13) +4*a(n-14) +2*a(n-15) -a(n-16) -a(n-17) -a(n-18)

Example

Some solutions for n=10
..1..1..0....1..0..0....1..0..0....0..1..1....1..1..0....0..1..1....1..0..1
..1..0..1....1..1..0....0..1..1....1..1..0....1..0..1....1..0..0....0..1..1
..0..1..0....0..0..0....1..1..0....1..0..1....0..1..0....0..1..1....1..0..0
..1..1..0....1..1..0....1..0..1....0..1..1....1..0..1....1..0..0....0..1..0
..0..0..0....1..1..0....0..1..0....1..0..0....0..1..0....0..1..1....1..1..0
..1..1..0....0..0..0....1..0..1....1..1..0....1..1..0....1..0..1....1..0..0
..0..0..0....1..1..0....0..1..1....0..0..0....1..0..0....0..0..0....0..1..0
..1..1..0....1..0..0....1..1..0....1..0..0....0..0..0....1..0..1....1..1..0
..1..0..0....0..1..0....1..0..1....1..0..0....1..0..0....1..0..1....1..0..0
..0..1..0....1..1..0....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..0..0....1..0..1....1..0..0....1..0..0....1..0..1....0..0..0
..0..0..0....1..0..0....1..0..1....0..0..0....1..0..0....1..0..0....0..0..0

Crossrefs

Sequence in context: A203091 A203084 A202378 * A195751 A072607 A306214

Adjacent sequences: A202368 A202369 A202370 * A202372 A202373 A202374

Keyword

nonn

Author

R. H. Hardin Dec 18 2011

Status

approved