A256729 Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum zero and no antidiagonal sum three

2304, 21904, 186624, 1648656, 14137600, 122323600, 1047687424, 9002973456, 77177284864, 662446232464, 5681548960000, 48744134890000, 418086024911104, 3586417795077264, 30762931758747904, 263883025624611600

Offset

1,1

Comments

Column 2 of A256735

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -39*a(n-2) -69*a(n-3) +1104*a(n-4) -4048*a(n-5) +3968*a(n-6) -19840*a(n-7) +92928*a(n-8) -52992*a(n-9) -98304*a(n-10) +180224*a(n-11) -393216*a(n-12) +2097152*a(n-13) -12582912*a(n-14) +16777216*a(n-15)

Example

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

Crossrefs

Cf. A256735

Sequence in context: A281927 A179699 A195652 * A204102 A177759 A218431

Adjacent sequences: A256726 A256727 A256728 * A256730 A256731 A256732

Keyword

nonn

Author

R. H. Hardin, Apr 09 2015

Status

approved