a(n) = (10^n - 9^n - 8^n - 7^n + 4*6^n)/2.
A081683
a(n) = (10^n - 9^n - 8^n - 7^n + 4*6^n)/2.
Terms
- a(0) =1a(1) =5a(2) =25a(3) =140a(4) =1063a(5) =11240a(6) =137695a(7) =1708040a(8) =20564863a(9) =239159480a(10) =2699431615a(11) =29751433640a(12) =321858414463
External references
- oeis: A081683