A191575 Number of n X n symmetric binary matrices with each 1 adjacent to no more than 7 knight-move neighboring 1s

2, 8, 64, 1024, 31744, 1966328, 243334360, 60208129728, 29758502758208, 29361656860572672, 57846064835261224704, 227511075000523635983456, 1786387499611617848051648112, 28002804481527546759736622292320

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..16

Example

Some solutions for n=6
..0..0..0..1..0..1....0..0..0..1..1..0....0..0..0..1..0..0....0..0..0..1..1..1
..0..0..0..0..1..0....0..0..0..0..1..0....0..0..0..1..0..1....0..0..1..1..0..1
..0..0..1..0..0..1....0..0..1..1..0..0....0..0..1..1..0..1....0..1..0..1..1..0
..1..0..0..0..1..1....1..0..1..0..1..0....1..1..1..1..1..0....1..1..1..1..0..0
..0..1..0..1..0..0....1..1..0..1..0..1....0..0..0..1..1..0....1..0..1..0..0..0
..1..0..1..1..0..0....0..0..0..0..1..0....0..1..1..0..0..1....1..1..0..0..0..0

Crossrefs

Sequence in context: A153544 A153572 A191574 * A153545 A153573 A153546

Adjacent sequences: A191572 A191573 A191574 * A191576 A191577 A191578

Keyword

nonn

Author

R. H. Hardin Jun 06 2011

Status

approved