Number of (n+1) X (3+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.
A251231
Number of (n+1) X (3+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.
Terms
- a(0) =322a(1) =694a(2) =1592a(3) =3886a(4) =9914a(5) =26224a(6) =71322a(7) =198318a(8) =561212a(9) =1611002a(10) =4679574a(11) =13730612a(12) =40642206a(13) =121238834a(14) =364209520a(15) =1101127798a(16) =3348686298a(17) =10239114144a(18) =31464490330a(19) =97136312190a(20) =301153069996a(21) =937321265322
External references
- oeis: A251231