Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 8 king-move adjacent elements, with upper left element zero.

A305240

Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 8 king-move adjacent elements, with upper left element zero.

Terms

    a(0) =4a(1) =12a(2) =18a(3) =32a(4) =86a(5) =158a(6) =343a(7) =721a(8) =1520a(9) =3228a(10) =6773a(11) =14334a(12) =30273a(13) =63871a(14) =134918a(15) =284843a(16) =601453a(17) =1270011a(18) =2681563a(19) =5662260a(20) =11955917a(21) =25245070a(22) =53305555a(23) =112555500a(24) =237663066a(25) =501829940a(26) =1059622929a(27) =2237413464a(28) =4724339318

External references