Number of multisets of nonempty words with a total of n letters over quaternary alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
A293734
Number of multisets of nonempty words with a total of n letters over quaternary 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) =3a(3) =7a(4) =20a(5) =53a(6) =157a(7) =455a(8) =1393a(9) =4270a(10) =13495a(11) =42907a(12) =139323a(13) =455182a(14) =1510831a(15) =5042858a(16) =17044789a(17) =57891598a(18) =198665585a(19) =684615958a(20) =2379765470a(21) =8302157207a(22) =29177909254a(23) =102867895209a(24) =364981305292
External references
- oeis: A293734