A249975 Number of length n+1 0..2*1 arrays with the sum of the absolute values of adjacent differences equal to n*1.

4, 10, 20, 64, 136, 466, 1012, 3580, 7864, 28340, 62696, 228700, 508400, 1870466, 4172660, 15449740, 34557400, 128583340, 288212440, 1076603824, 2417218544, 9058241620, 20366034760, 76521687304, 172247070064, 648634854904

Offset: 1

Author

R. H. Hardin, Nov 10 2014

Keywords

• nonn

Comments

Column 1 of A249982

Examples

			Some solutions for n=6
..1....0....1....0....0....0....1....2....0....1....0....0....2....0....0....0
..2....1....2....0....2....2....1....1....0....2....2....1....0....1....1....0
..0....2....1....1....1....1....0....2....1....0....1....2....2....0....1....0
..1....1....1....0....0....2....2....2....0....0....2....2....1....1....0....2
..0....2....0....1....1....1....0....0....2....1....2....1....1....0....2....1
..1....1....2....2....1....0....0....0....0....2....0....0....0....1....2....0
..1....0....1....0....2....0....1....2....0....1....0....2....0....2....0....2
		

Links

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