A207173 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.

10, 100, 270, 1161, 3445, 8455, 26908, 82861, 228060, 672760, 2029041, 5846337, 17039101, 50518174, 147655795, 430953736, 1267685262, 3717105229, 10874111625, 31898934243, 93554384968, 274033182253, 803273682808, 2355253402240

Offset

1,1

Comments

Row 5 of A207169.

Links

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

Formula

Empirical: a(n) = a(n-1) + 17*a(n-3) + 4*a(n-4) + 4*a(n-5) - 48*a(n-6) - 32*a(n-7) + 64*a(n-9) for n>11.

Empirical g.f.: x*(10 + 90*x + 170*x^2 + 721*x^3 + 544*x^4 - 20*x^5 - 2284*x^6 - 3216*x^7 - 800*x^8 + 3392*x^9 + 2304*x^10) / ((1 - 2*x - 8*x^3)*(1 + x + 2*x^2 - 5*x^3 - 6*x^4 + 8*x^6)). - Colin Barker, Jun 20 2018

Example

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

Crossrefs

Cf. A207169.

Sequence in context: A095920 A207602 A207028 * A207456 A208836 A208684

Adjacent sequences: A207170 A207171 A207172 * A207174 A207175 A207176

Keyword

nonn

Author

R. H. Hardin, Feb 15 2012

Status

approved