Average of two consecutive odd primes.

Terms

a(0) =4a(1) =6a(2) =9a(3) =12a(4) =15a(5) =18a(6) =21a(7) =26a(8) =30a(9) =34a(10) =39a(11) =42a(12) =45a(13) =50a(14) =56a(15) =60a(16) =64a(17) =69a(18) =72a(19) =76a(20) =81a(21) =86a(22) =93a(23) =99a(24) =102a(25) =105a(26) =108a(27) =111a(28) =120a(29) =129