A210834 Number of (n+1) X (n+1) 0..3 symmetric matrices with every 2 X 2 subblock having one, two or four distinct values, and new values 0..3 introduced in lower triangle row major order.

4, 51, 1675, 125483, 20178747, 6756016331, 4647730539387, 6537458079419739, 18773661532321526331, 110047493954215211056859

Offset

1,1

Links

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

Example

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

Crossrefs

Sequence in context: A300732 A220282 A235326 * A287231 A289708 A000516

Adjacent sequences: A210831 A210832 A210833 * A210835 A210836 A210837

Keyword

nonn

Author

R. H. Hardin Mar 27 2012

Status

approved