Numerators of partial sums of reciprocals of lcm(1..n) = A003418(n).

Terms

a(0) =1a(1) =3a(2) =5a(3) =7a(4) =53a(5) =107a(6) =25a(7) =1501a(8) =563a(9) =901a(10) =12389a(11) =16519a(12) =322121a(13) =644243a(14) =53687a(15) =1288489a(16) =3650719a(17) =4380863a(18) =18917363a(19) =3557111a(20) =104045497a(21) =416181989a(22) =2393046437a(23) =455818369a(24) =23930464373a(25) =47860928747a(26) =10255913303a(27) =11044829711