A145775 - OEIS

A145775

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

%I #3 Mar 31 2012 12:35:08

%S 1,1,1,4,10,25,98,304,1809,7930,72506,400613,5713422,40142648,

%T 888016669,8057185631,274304468798,3201392865337,169069430683773,

%U 2534673576738596,207045671219200314,3988243193242437962,504059170133969414707

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

%K nonn

%O 1,4

%A _R. H. Hardin_, Oct 18 2008