Number of n-letter strings over a ten-letter alphabet where no letter appears exactly four times.
A272502
Number of n-letter strings over a ten-letter alphabet where no letter appears exactly four times.
Terms
- a(0) =1a(1) =10a(2) =100a(3) =1000a(4) =9990a(5) =99550a(6) =987850a(7) =9744850a(8) =95410450a(9) =925825060a(10) =8893045900a(11) =84482314300a(12) =793301261050
External references
- oeis: A272502