Number of optimal binary prefix-free codes with n words all ending in 1.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =4a(7) =5a(8) =7a(9) =9a(10) =13a(11) =17a(12) =23a(13) =30a(14) =39a(15) =50a(16) =65a(17) =83a(18) =107a(19) =136a(20) =174a(21) =219a(22) =278a(23) =348a(24) =437a(25) =544a(26) =678a(27) =839a(28) =1039a(29) =1279