Number of sets of nonempty words with a total of n letters over septenary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
A293746
Number of sets of nonempty words with a total of n letters over septenary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =15a(5) =45a(6) =136a(7) =430a(8) =1414a(9) =4835a(10) =17143a(11) =62843a(12) =238245a(13) =930418a(14) =3741710a(15) =15445815a(16) =65384356a(17) =283113205a(18) =1252393193a(19) =5648731817a(20) =25945636702a(21) =121172059749a(22) =574764521186
External references
- oeis: A293746