A299593 Number of n X 6 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
13, 15, 35, 121, 256, 576, 1225, 2601, 5625, 12100, 25921, 55696, 119716, 257049, 552049, 1185921, 2547216, 5470921, 11751184, 25240576, 54213769, 116445681, 250114225, 537219684, 1153892961, 2478446656, 5323453444, 11434238761
Offset: 1
Keywords
Examples
Some solutions for n=5: ..0..0..0..1..0..0. .0..0..0..0..0..0. .0..0..0..1..0..0. .0..0..0..0..0..0 ..1..0..0..0..0..1. .1..0..0..0..0..1. .1..0..0..0..0..0. .1..0..0..0..0..1 ..0..0..0..0..0..0. .0..0..0..0..0..0. .0..0..0..0..0..0. .0..0..0..0..0..0 ..0..0..0..0..0..0. .0..0..0..0..0..0. .0..0..0..0..0..0. .0..0..0..0..0..0 ..0..1..0..0..0..0. .0..0..1..0..0..0. .0..1..0..0..1..0. .0..1..0..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A299595.
Formula
Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +a(n-4) -a(n-5) -a(n-6) for n>9.
Empirical g.f.: x*(13 + 2*x + 7*x^2 + 32*x^3 + 42*x^4 + 92*x^5 + 23*x^6 - 39*x^7 - 29*x^8) / ((1 + x^2 - x^3)*(1 - x - 2*x^2 - x^3)). - Colin Barker, Feb 15 2018
Comments