A232590 Number of (1+1)X(n+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally, with no adjacent elements equal

0, 10, 2, 26, 20, 70, 90, 210, 336, 674, 1178, 2234, 4036, 7502, 13714, 25314, 46464, 85562, 157266, 289370, 532116, 978838, 1800234, 3311282, 6090256, 11201874, 20603306, 37895546, 69700612, 128199582, 235795618, 433695938, 797691008

Offset

1,2

Comments

Row 1 of A232589

Links

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

Formula

Empirical: a(n) = -a(n-1) +2*a(n-2) +4*a(n-3) +3*a(n-4) +a(n-5).

Empirical: G.f.: -2*x^2*(5+6*x+4*x^2+x^3) / ( (x^3+x^2+x-1)*(1+x)^2 ). - R. J. Mathar, Nov 23 2014

Example

Some solutions for n=7
..0..1..2..1..0..1..2..0....0..1..2..1..2..1..0..2....0..1..2..1..2..0..1..2
..2..1..0..1..2..0..1..2....0..1..0..1..0..2..1..0....2..1..0..1..2..0..1..0

Crossrefs

Sequence in context: A086068 A262557 A030595 * A094715 A213555 A305995

Adjacent sequences: A232587 A232588 A232589 * A232591 A232592 A232593

Keyword

nonn

Author

R. H. Hardin, Nov 26 2013

Status

approved