A202956 Number of arrays of n+2 integers in -2..2 with sum zero and adjacent elements differing in absolute value.

6, 28, 82, 200, 524, 1724, 5908, 18340, 53680, 162080, 515626, 1651124, 5168256, 15997588, 50018962, 158377344, 502147864, 1584312736, 4991421852, 15779264936, 50053153920, 158866891408, 503893624892, 1598691706648, 5078888702164

Offset: 1

Author

R. H. Hardin, Dec 26 2011

Keywords

• nonn

Comments

Column 2 of A202962.

Examples

			Some solutions for n=5
..0....2....0...-1....2....2...-1....1...-1...-1...-2....0....2....0....0....2
.-1....0...-2....0....0....0....2...-2...-2....0....0...-1....0...-2....1....0
..2...-2....1...-1....2...-2...-1....1....1...-2...-1...-2....1...-1...-2...-1
..0...-1....0....0...-1...-1....2....0...-2....0....2....0....0....2...-1....2
.-2....0...-1....1...-2....0...-1...-1....1....1....0....2...-1...-1....0...-1
..0...-1....2....0....0....1....0....2....2....2...-1....1....0....2....2...-2
..1....2....0....1...-1....0...-1...-1....1....0....2....0...-2....0....0....0
		

Links

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

Crossrefs

Cf. A202962.