Number of length n arrays x(i), i=1..n with x(i) in i..i+3 and no value appearing more than 2 times.
A250346
Number of length n arrays x(i), i=1..n with x(i) in i..i+3 and no value appearing more than 2 times.
Terms
- a(0) =4a(1) =16a(2) =62a(3) =235a(4) =888a(5) =3349a(6) =12620a(7) =47545a(8) =179104a(9) =674666a(10) =2541362a(11) =9572864a(12) =36059224a(13) =135828387a(14) =511640114a(15) =1927252354a(16) =7259597884a(17) =27345542237a(18) =103005522894a(19) =388002462425
External references
- oeis: A250346