A257354 Number of (n+2)X(1+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum less than the central column sum

220, 784, 3108, 12100, 45684, 174724, 674856, 2585664, 9853288, 37724164, 144911780, 555167844, 2122710008, 8128825600, 31164354584, 119371632004, 456940637076, 1750016785924, 6704844968808, 25680650841664, 98339620401640

Offset

1,1

Comments

Column 1 of A257361

Links

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

Formula

Empirical: a(n) = a(n-1) +15*a(n-3) +75*a(n-4) +64*a(n-5) +86*a(n-6) +100*a(n-7) +440*a(n-8) +200*a(n-9) -344*a(n-10) -96*a(n-11) +1200*a(n-12) +800*a(n-13) -384*a(n-15) -256*a(n-16)

Example

Some solutions for n=4
..0..1..1....1..0..1....0..1..1....1..1..0....0..0..0....1..0..0....1..1..0
..1..0..0....1..1..1....0..1..1....1..0..1....0..0..1....1..0..0....1..0..1
..1..0..0....1..0..0....1..0..0....1..0..1....1..0..0....0..1..1....1..0..1
..1..0..1....1..0..0....1..0..0....1..0..0....1..1..0....1..1..1....0..0..1
..0..0..1....1..1..1....1..0..1....1..1..0....0..1..1....1..1..1....1..1..0
..0..0..1....0..1..1....1..0..1....0..1..0....1..0..1....0..0..1....0..0..0

Crossrefs

Cf. A257361

Sequence in context: A258545 A257361 A258538 * A102073 A234969 A002025

Adjacent sequences: A257351 A257352 A257353 * A257355 A257356 A257357

Keyword

nonn

Author

R. H. Hardin, Apr 20 2015

Status

approved