Number of sets of nonempty words with a total of n letters over ternary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
A293742
Number of sets of nonempty words with a total of n letters over ternary 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) =14a(5) =39a(6) =104a(7) =284a(8) =775a(9) =2145a(10) =5941a(11) =16563a(12) =46329a(13) =130100a(14) =366432a(15) =1035191a(16) =2931797a(17) =8323290a(18) =23680142a(19) =67505721a(20) =192791938a(21) =551537506a(22) =1580315319a(23) =4534715008a(24) =13030197881a(25) =37489497472a(26) =107991978290a(27) =311433926717a(28) =899093131819
External references
- oeis: A293742