A234778 Number of (n+1)X(n+1) 0..3 arrays with no adjacent elements equal and with each 2X2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases

76, 6660, 2761748, 5465582060, 51845281856108, 2363085244017636364, 518342328616619031217020, 547728179121316322465056282212, 2790190676549838064460970840259520660

Offset

1,1

Comments

Diagonal of A234786

Links

R. H. Hardin, Table of n, a(n) for n = 1..10

Example

Some solutions for n=2
..2..3..1....3..2..1....1..2..3....0..3..2....2..1..3....3..1..3....3..0..1
..3..1..0....1..0..2....0..1..2....3..2..0....1..0..2....0..2..1....0..2..3
..1..2..1....3..2..1....1..2..1....0..3..2....0..2..3....3..0..2....2..0..2

Crossrefs

Sequence in context: A004299 A049669 A198476 * A139671 A098606 A093276

Adjacent sequences: A234775 A234776 A234777 * A234779 A234780 A234781

Keyword

nonn

Author

R. H. Hardin, Dec 30 2013

Status

approved