Number of nX3 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
A280805
Number of nX3 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
Terms
- a(0) =0a(1) =3a(2) =56a(3) =332a(4) =1578a(5) =6540a(6) =24490a(7) =86010a(8) =288426a(9) =933792a(10) =2940425a(11) =9053479a(12) =27364145a(13) =81436340a(14) =239191322a(15) =694661663a(16) =1997809427a(17) =5696648777a(18) =16121608346a(19) =45319683250a(20) =126637762818a(21) =351964959409a(22) =973463999825
External references
- oeis: A280805