Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 5-point barb 1,1 1,2 2,2 2,3 3,2 in any orientation.

A146143

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 5-point barb 1,1 1,2 2,2 2,3 3,2 in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =13a(5) =51a(6) =327a(7) =1743a(8) =13905a(9) =216443a(10) =3286293a(11) =80038799a(12) =2242888197a(13) =93345565591

External references