One third of the sum of the first n primes, when an integer.

Terms

a(0) =43a(1) =127a(2) =167a(3) =213a(4) =321a(5) =387a(6) =457a(7) =531a(8) =617a(9) =709a(10) =809a(11) =1029a(12) =1149a(13) =1277a(14) =1409a(15) =1863a(16) =2027a(17) =2290a(18) =3397a(19) =3629a(20) =4113a(21) =4367a(22) =4629a(23) =4899a(24) =5179a(25) =5467a(26) =5761a(27) =6063a(28) =6371a(29) =7516