Number of nX2 0..1 arrays with every element unequal to 0, 1, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A318031

Number of nX2 0..1 arrays with every element unequal to 0, 1, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =2a(1) =3a(2) =6a(3) =11a(4) =22a(5) =46a(6) =91a(7) =182a(8) =371a(9) =746a(10) =1498a(11) =3027a(12) =6102a(13) =12283a(14) =24766a(15) =49926a(16) =100587a(17) =202726a(18) =408611a(19) =823442a(20) =1659506a(21) =3344611a(22) =6740518a(23) =13584427a(24) =27377702a(25) =55175838a(26) =111198651a(27) =224105366a(28) =451652627a(29) =910240506

External references