Number of n X 4 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 neighboring 1s.

A297427

Number of n X 4 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 neighboring 1s.

Terms

    a(0) =1a(1) =12a(2) =26a(3) =42a(4) =183a(5) =513a(6) =1085a(7) =3332a(8) =9744a(9) =23836a(10) =65693a(11) =187681a(12) =491757a(13) =1322824a(14) =3682514a(15) =9913750a(16) =26662827a(17) =73102697a(18) =198448393a(19) =535843320a(20) =1459128416a(21) =3966961416a(22) =10743629897a(23) =29183372609a(24) =79314611625a(25) =215140998420

External references