A208115 Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

15, 225, 825, 3025, 7315, 17689, 34713, 68121, 117711, 203401, 322465, 511225, 761475, 1134225, 1611345, 2289169, 3133423, 4289041, 5697321, 7568001, 9807315, 12709225, 16131625, 20475625, 25534575, 31843449, 39111633, 48038761, 58227331

Offset

1,1

Comments

Column 5 of A208118.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12).

Empirical g.f.: x*(15 + 195*x + 315*x^2 + 625*x^3 + 290*x^4 + 34*x^5 - 50*x^6 + 14*x^7 + 7*x^8 - 5*x^9 - x^10 + x^11) / ((1 - x)^7*(1 + x)^5). - Colin Barker, Jun 28 2018

Example

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

Crossrefs

Cf. A208118.

Sequence in context: A208105 A207726 A207596 * A267784 A207700 A207905

Adjacent sequences: A208112 A208113 A208114 * A208116 A208117 A208118

Keyword

nonn

Author

R. H. Hardin, Feb 23 2012

Status

approved