Cardinality of the smallest nonempty class of length minimal languages with exactly n nonempty words each over a countably infinite alphabet such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
A291057
Cardinality of the smallest nonempty class of length minimal languages with exactly n nonempty words each over a countably infinite 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) =1a(4) =4a(5) =6a(6) =4a(7) =1a(8) =10a(9) =45a(10) =120a(11) =210a(12) =252a(13) =210a(14) =120a(15) =45a(16) =10a(17) =1a(18) =26a(19) =325a(20) =2600a(21) =14950a(22) =65780a(23) =230230a(24) =657800a(25) =1562275a(26) =3124550a(27) =5311735a(28) =7726160a(29) =9657700
External references
- oeis: A291057