login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A252771
Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row, column and nw-se diagonal having exactly two distinct values, and new values 0 upwards introduced in row major order
1
234, 1028, 4687, 22295, 105956, 507049, 2429173, 11652188, 55960799, 268783174, 1291581364, 6207376902, 29836567197, 143422264585, 689472936242, 3314565767875, 15934867914351, 76608704638459, 368308600684650
OFFSET
1,1
COMMENTS
Column 1 of A252777
FORMULA
Empirical recurrence of order 63 (see link above)
EXAMPLE
Some solutions for n=4
..0..0..1....0..0..1....0..0..1....0..1..1....0..1..1....0..0..1....0..1..1
..2..1..2....1..2..2....1..2..2....1..2..1....1..2..1....1..0..1....2..1..1
..2..1..1....0..0..2....0..0..2....1..1..0....0..2..0....1..2..2....0..2..0
..1..3..1....0..2..0....1..2..1....0..2..0....0..1..1....0..2..2....0..1..1
..1..3..3....1..2..2....1..2..2....0..2..2....3..1..1....1..0..1....2..2..1
..3..2..3....1..1..2....0..0..2....2..0..0....3..3..0....0..2..2....0..1..0
CROSSREFS
Sequence in context: A287878 A252338 A252777 * A251515 A251508 A185482
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 21 2014
STATUS
approved