Number of n X n 0..1 arrays with every element unequal to 0, 1 or 3 king-move adjacent elements, with upper left element zero.

A303676

Number of n X n 0..1 arrays with every element unequal to 0, 1 or 3 king-move adjacent elements, with upper left element zero.

Terms

    a(0) =1a(1) =5a(2) =9a(3) =28a(4) =76a(5) =177a(6) =367a(7) =774a(8) =1684a(9) =3639a(10) =7597a(11) =15617a(12) =32101a(13) =66074a(14) =135096a(15) =274104a(16) =553668a(17) =1116275a(18) =2245277a(19) =4501938a(20) =9000074a(21) =17953486a(22) =35749382a(23) =71056212a(24) =140977366a(25) =279246077a(26) =552333115a(27) =1091040731

External references