Number of ways to reciprocally link elements of an nX3 array either to themselves or to exactly two king-move neighbors, without 3-loops.

A220648

Number of ways to reciprocally link elements of an nX3 array either to themselves or to exactly two king-move neighbors, without 3-loops.

Terms

    a(0) =1a(1) =23a(2) =333a(3) =4352a(4) =59846a(5) =816159a(6) =11131560a(7) =151872860a(8) =2071881506a(9) =28265332768a(10) =385605987981

External references