A206234 Number of (n+1) X 5 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly two equal edges, and new values 0..3 introduced in row major order.
1640, 5728, 27168, 283728, 1236432, 9042600, 95322432, 419146392, 3065437344, 32314300392, 142090622832, 1039183255560, 10954547828832, 48168721135992, 352283123630784, 3713591713969992, 16329196465097232, 119423978910831720
Offset: 1
Keywords
Examples
Some solutions for n=4: ..0..0..1..1..2....0..0..1..2..0....0..0..1..1..2....0..1..0..0..2 ..1..1..2..1..1....0..3..2..2..0....1..1..2..1..1....2..0..0..3..0 ..2..1..1..2..1....3..2..2..0..1....3..1..1..2..1....0..0..1..0..0 ..3..0..1..1..2....2..2..3..1..1....1..2..1..1..2....3..3..0..0..3 ..3..3..2..1..2....2..3..1..1..0....1..1..2..1..1....1..3..0..1..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A206238.
Formula
Empirical: a(n) = a(n-1) + 339*a(n-3) - 339*a(n-4) for n>8.
Empirical g.f.: 8*x*(205 + 511*x + 2680*x^2 - 37425*x^3 - 54141*x^4 + 67251*x^5 - 86751*x^6 + 107163*x^7) / ((1 - x)*(1 - 339*x^3)). - Colin Barker, Jun 14 2018
Comments