A282964 Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements.

0, 5, 38, 309, 2012, 12160, 70722, 395223, 2150350, 11454117, 59948615, 309270883, 1576188831, 7949681739, 39734943909, 197045928939, 970369807931, 4749163345697, 23114719065210, 111941467863241, 539671083601641

Offset

1,2

Comments

Column 3 of A282969.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +24*a(n-2) +7*a(n-3) -267*a(n-4) -870*a(n-5) -639*a(n-6) +3738*a(n-7) +16311*a(n-8) +37667*a(n-9) +61221*a(n-10) +74643*a(n-11) +67169*a(n-12) +38199*a(n-13) -30*a(n-14) -29442*a(n-15) -38079*a(n-16) -27174*a(n-17) -8230*a(n-18) +6285*a(n-19) +10539*a(n-20) +6972*a(n-21) +1605*a(n-22) -1506*a(n-23) -1799*a(n-24) -753*a(n-25) +57*a(n-26) +265*a(n-27) +111*a(n-28) +3*a(n-29) -24*a(n-30) -6*a(n-31) +a(n-33)

Example

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

Crossrefs

Cf. A282969.

Sequence in context: A110079 A110082 A073508 * A357163 A357224 A247773

Adjacent sequences: A282961 A282962 A282963 * A282965 A282966 A282967

Keyword

nonn

Author

R. H. Hardin, Feb 25 2017

Status

approved