A205583 Number of (n+1) X 2 0..2 arrays with no 2 X 2 subblock having the same number of equal edges as its horizontal or vertical neighbors, and new values 0..2 introduced in row major order.
14, 74, 413, 2268, 12574, 69338, 383440, 2117054, 11699556, 64620690, 357034452, 1972284262, 10896200940, 60194058786, 332543162084, 1837101323030, 10149009487404, 56067475332178, 309742091323076, 1711151039052838
Offset: 1
Keywords
Examples
Some solutions for n=4: ..0..1....0..0....0..1....0..0....0..0....0..0....0..0....0..1....0..1....0..1 ..1..1....1..2....0..2....0..1....0..1....1..1....1..2....2..2....2..0....2..0 ..0..2....0..1....2..0....2..0....2..1....1..1....2..2....1..2....1..0....0..0 ..2..2....1..1....0..0....1..0....2..1....1..0....1..0....0..2....2..1....2..1 ..1..0....2..0....1..2....0..2....0..1....1..2....1..1....2..2....0..1....2..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A205590.
Formula
Empirical: a(n) = 21*a(n-2) + 44*a(n-3) + 50*a(n-4) + 12*a(n-5) - 144*a(n-6) for n>7.
Empirical g.f.: x*(14 + 74*x + 119*x^2 + 98*x^3 - 55*x^4 - 330*x^5 + 72*x^6) / (1 - 21*x^2 - 44*x^3 - 50*x^4 - 12*x^5 + 144*x^6). - Colin Barker, Mar 04 2018
Comments