A218838 Unmatched value maps: number of n X 4 binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 n X 4 array.

7, 57, 453, 3617, 28888, 230726, 1842766, 14717828, 117548611, 938839259, 7498337380, 59887849061, 478313295496, 3820200795065, 30511244937310, 243687732023270, 1946289338913085, 15544656923507264, 124152331330394548

Offset

1,1

Comments

Column 4 of A218842.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 7*a(n-1) + 5*a(n-2) + 24*a(n-3) - 9*a(n-4) + 9*a(n-5) for n>6.

Empirical g.f.: x*(7 + 8*x + 19*x^2 - 7*x^3 - x^4 + 3*x^5) / (1 - 7*x - 5*x^2 - 24*x^3 + 9*x^4 - 9*x^5). - Colin Barker, Mar 10 2018

Example

Some solutions for n=3:
..0..0..0..0....1..1..0..0....1..0..0..0....1..1..0..0....1..0..0..1
..1..0..1..1....1..0..0..1....1..0..0..0....1..0..0..0....0..0..1..1
..1..1..0..0....1..0..0..0....0..0..1..1....1..0..1..1....1..1..1..1

Crossrefs

Cf. A218842.

Sequence in context: A042187 A201872 A218587 * A082310 A014990 A015565

Adjacent sequences: A218835 A218836 A218837 * A218839 A218840 A218841

Keyword

nonn

Author

R. H. Hardin, Nov 07 2012

Status

approved