A145791 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only either four adjacent vertically or four adjacent horizontally.

1, 1, 1, 3, 1, 6, 1, 17, 26, 113, 318, 1310, 4072, 21570, 65328, 442636, 1558383, 13750703, 69409037, 646392443, 4686057331, 48049954607, 457665821401, 5254108049909, 63960030819910, 855193502729867

Offset

1,4

Links

Table of n, a(n) for n=1..26.

Crossrefs

Sequence in context: A165552 A067231 A218971 * A348661 A322041 A130302

Adjacent sequences: A145788 A145789 A145790 * A145792 A145793 A145794

Keyword

nonn

Author

R. H. Hardin, Oct 19 2008

Status

approved