A203980 Number of (n+1) X 5 0..2 arrays with no 2 X 2 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..2 introduced in row major order.
384, 5184, 69984, 956448, 13071456, 178855776, 2447270496, 33489653472, 458288894304, 6271519652064, 85823503984224, 1174465206026208, 16072153386090336, 219941927082883296, 3009830115907061856
Offset: 1
Keywords
Examples
Some solutions for n=4: ..0..1..1..2..0....0..1..1..1..1....0..1..1..1..1....0..1..2..1..2 ..2..2..0..2..0....2..2..2..2..0....2..2..2..2..0....2..1..2..1..2 ..0..1..1..2..1....1..0..0..1..1....1..0..1..1..0....0..0..2..0..2 ..0..2..0..2..0....2..2..2..2..2....1..0..2..2..2....2..1..1..1..1 ..0..1..0..1..0....0..1..0..1..0....1..0..1..0..1....0..0..0..0..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A203984.
Formula
Empirical: a(n) = 15*a(n-1) - 270*a(n-3) + 324*a(n-4).
Empirical g.f.: 96*x*(4 - 6*x - 81*x^2 + 108*x^3) / ((1 - 15*x + 18*x^2)*(1 - 18*x^2)). - Colin Barker, Jun 06 2018
Comments