A219004 Unmatched value maps: number of 3 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal, diagonal or antidiagonal neighbor in a random 0..2 3 X n array.
1, 36, 328, 2265, 16648, 127401, 966981, 7298225, 55135016, 416848560, 3151246505, 23819866072, 180053403609, 1361036722345, 10288162925081, 77768717139628, 587857527338664, 4443644969933825, 33589738253657200, 253906529656115169
Offset: 1
Keywords
Examples
Some solutions for n=3: ..1..1..0....0..0..1....0..1..0....1..1..1....0..0..1....1..1..0....0..0..0 ..0..0..1....0..1..1....0..0..0....1..0..0....1..0..0....1..0..1....1..1..1 ..1..1..0....1..0..0....0..0..0....1..1..1....1..0..0....0..1..0....1..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..42
Crossrefs
Cf. A219002.
Formula
Empirical: a(n) = 7*a(n-1) - 3*a(n-2) + 49*a(n-3) + 45*a(n-4) - 17*a(n-5) - 15*a(n-6).
Empirical g.f.: x*(1 + 29*x + 79*x^2 + 28*x^3 - 32*x^4 - 15*x^5) / (1 - 7*x + 3*x^2 - 49*x^3 - 45*x^4 + 17*x^5 + 15*x^6). - Colin Barker, Jul 25 2018
Comments