A250163 Number of length n+1 0..4 arrays with the sum of adjacent differences multiplied by some arrangement of +-1 equal to zero.

5, 33, 211, 1269, 7109, 37881, 195927, 996933, 5029417, 25262121, 126608171, 633821781, 3171197325, 15861685497, 79324281727, 396666275397, 1983460173617, 9917674841193, 49589469690579, 247950578857365, 1239762467069077

Offset: 1

Author

R. H. Hardin, Nov 13 2014

Keywords

• nonn

Examples

			Some solutions for n=6:
..3....0....1....0....1....2....0....4....4....4....1....3....4....1....1....0
..2....1....0....0....2....3....4....1....4....3....1....0....2....3....3....4
..3....1....4....2....3....2....0....0....1....0....3....2....4....4....0....3
..2....2....2....1....3....0....0....0....0....0....4....4....1....2....4....0
..0....0....4....3....1....4....3....1....4....2....4....1....3....4....3....1
..2....0....2....1....3....0....1....2....2....2....3....2....2....3....2....2
..3....2....3....0....3....0....2....2....4....0....1....3....0....3....1....2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..55

Crossrefs

Column 4 of A250167.

Formula

Empirical: a(n) = 16*a(n-1) -105*a(n-2) +372*a(n-3) -783*a(n-4) +1008*a(n-5) -779*a(n-6) +332*a(n-7) -60*a(n-8).

Empirical g.f.: x*(5 - 47*x + 208*x^2 - 502*x^3 + 599*x^4 - 311*x^5 + 52*x^6 + 44*x^7) / ((1 - x)^4*(1 - 2*x)^2*(1 - 3*x)*(1 - 5*x)). - Colin Barker, Nov 12 2018