Equals two maps: number of 2Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 2Xn array.
A220329
Equals two maps: number of 2Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 2Xn array.
Terms
- a(0) =1a(1) =4a(2) =16a(3) =48a(4) =174a(5) =658a(6) =2482a(7) =9229a(8) =33982a(9) =125217a(10) =461351a(11) =1699127a(12) =6252129a(13) =22995280a(14) =84546207a(15) =310785413a(16) =1142206689a(17) =4197260747a(18) =15421867303a(19) =56659522539a(20) =208152496049a(21) =764662949438
External references
- oeis: A220329