A255143 Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 and no antidiagonal sum 0 and no row sum 1 and no column sum 1

115, 371, 1310, 4576, 16386, 59681, 217262, 791181, 2886865, 10536452, 38448744, 140326648, 512194269, 1869459662, 6823369543, 24905092259, 90902668054, 331790760244, 1211023928212, 4420193626025, 16133540310758, 58886821611133

Offset

1,1

Comments

Column 2 of A255149

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +a(n-2) +14*a(n-3) -20*a(n-4) -38*a(n-5) -57*a(n-6) +32*a(n-7) +181*a(n-8) +161*a(n-9) -27*a(n-10) -301*a(n-11) -250*a(n-12) -15*a(n-13) +250*a(n-14) +170*a(n-15) +33*a(n-16) -94*a(n-17) -50*a(n-18) -18*a(n-19) +18*a(n-20) +4*a(n-22)

Example

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

Crossrefs

Cf. A255149

Sequence in context: A340098 A208815 A334345 * A154070 A251215 A218324

Adjacent sequences: A255140 A255141 A255142 * A255144 A255145 A255146

Keyword

nonn

Author

R. H. Hardin, Feb 15 2015

Status

approved