Number of length-(n+1) 0..4 arrays with new values introduced in sequential order, and with new repeated values introduced in sequential order, both starting with zero.
A268323
Number of length-(n+1) 0..4 arrays with new values introduced in sequential order, and with new repeated values introduced in sequential order, both starting with zero.
Terms
- a(0) =2a(1) =4a(2) =11a(3) =33a(4) =113a(5) =418a(6) =1644a(7) =6729a(8) =28306a(9) =121290a(10) =526528a(11) =2307684a(12) =10189912a(13) =45272176a(14) =202209217a(15) =907511800a(16) =4091094290a(17) =18521091171a(18) =84191453893a(19) =384234672892
External references
- oeis: A268323