A141488 Number of n X n binary matrices, symmetric under 180 degree rotation, with no more than 1 one in any 2 X 2 subblock.

1, 2, 1, 7, 14, 111, 277, 4630, 25913, 702227, 6394908, 326629617, 5687827965, 509730678546, 15540557303649, 2543316661538595, 142034694045640208, 41602235282780689163, 4154045153554082019959, 2201424142622929530965310

Offset

0,2

Links

R. H. Hardin, Aug 09 2008, Table of n, a(n) for n = 0..24

Yüksel Soykan, Sum Formulas for Generalized Fifth-Order Linear Recurrence Sequences, Journal of Advances in Mathematics and Computer Science (2019) Vol. 34, No. 5, 1-14.

Crossrefs

Sequence in context: A095137 A239104 A260259 * A113042 A305881 A184346

Adjacent sequences: A141485 A141486 A141487 * A141489 A141490 A141491

Keyword

nonn

Author

R. H. Hardin, Aug 09 2008

Status

approved