Number of length n word structures with all distinct run-lengths using an infinite alphabet.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =3a(5) =5a(6) =17a(7) =19a(8) =31a(9) =45a(10) =177a(11) =191a(12) =335a(13) =469a(14) =733a(15) =2679a(16) =3063a(17) =5129a(18) =7445a(19) =11431a(20) =15667a(21) =59025a(22) =65301a(23) =112379a(24) =159827a(25) =248185a(26) =336913a(27) =505683a(28) =1660611a(29) =1909901