A250968 Number of (n+1)X(3+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements less than the absolute difference of its antidiagonal elements

172, 1945, 22048, 249921, 2833397, 32124018, 364210219, 4129278507, 46816221866, 530784935436, 6017842440934, 68228062145830, 773544424316648, 8770159340495832, 99432808820402153, 1127332250873994176

Offset

1,1

Comments

Column 3 of A250973

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -68*a(n-2) +210*a(n-3) -492*a(n-4) +705*a(n-5) -675*a(n-6) +389*a(n-7) -120*a(n-8) +20*a(n-9)

Example

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

Crossrefs

Sequence in context: A234992 A213992 A214115 * A264213 A250340 A035828

Adjacent sequences: A250965 A250966 A250967 * A250969 A250970 A250971

Keyword

nonn

Author

R. H. Hardin, Nov 29 2014

Status

approved