Number of distinct primes in the numerator of the 2^n sums generated from the set 1, 1/2, 1/3, ..., 1/n.

A075189

Number of distinct primes in the numerator of the 2^n sums generated from the set 1, 1/2, 1/3, ..., 1/n.

Terms

    a(0) =0a(1) =1a(2) =3a(3) =6a(4) =14a(5) =20a(6) =38a(7) =74a(8) =134a(9) =232a(10) =486a(11) =526a(12) =1078a(13) =2036a(14) =2505a(15) =4762a(16) =9929a(17) =14598a(18) =29831a(19) =31521a(20) =52223a(21) =101123a(22) =207892a(23) =215796a(24) =426772a(25) =836665a(26) =1640357a(27) =1689653a(28) =3401483a(29) =3471770

External references