A281053 Number of nX5 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

2, 104, 618, 2452, 7803, 22106, 58005, 144283, 344972, 800225, 1812024, 4023754, 8791481, 18948288, 40366695, 85135873, 177990242, 369259703, 760850914, 1558181104, 3173635543, 6432024694, 12977428633, 26076680087, 52202242904

Offset

1,1

Comments

Column 5 of A281056.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +5*a(n-4) +9*a(n-5) -12*a(n-7) -3*a(n-8) +3*a(n-9) +6*a(n-10) -a(n-12) -a(n-13) for n>16

Example

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

Crossrefs

Cf. A281056.

Sequence in context: A106299 A176933 A246775 * A101530 A199945 A346165

Adjacent sequences: A281050 A281051 A281052 * A281054 A281055 A281056

Keyword

nonn

Author

R. H. Hardin, Jan 13 2017

Status

approved