Half the number of (n+1) X 3 binary arrays with no 2 X 2 subblock having exactly 2 ones.

A183775

Half the number of (n+1) X 3 binary arrays with no 2 X 2 subblock having exactly 2 ones.

Terms

    a(0) =4a(1) =13a(2) =47a(3) =161a(4) =567a(5) =1969a(6) =6887a(7) =24001a(8) =83799a(9) =292305a(10) =1020103a(11) =3559137a(12) =12419383a(13) =43333873a(14) =151206055a(15) =527598593a(16) =1840949015a(17) =6423592977a(18) =22413786247a(19) =78208138529a(20) =272890816759a(21) =952194714417

External references