Number of n-length words w over a 10-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z.
A240616
Number of n-length words w over a 10-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =14a(5) =46a(6) =165a(7) =651a(8) =2771a(9) =12638a(10) =61398a(11) =315562a(12) =1709960a(13) =9723253a(14) =57831688a(15) =358445901a(16) =2306799588a(17) =15354546420a(18) =105275618325a(19) =740481162174
External references
- oeis: A240616