n*10^7-1, n*10^7-3, n*10^7-7 and n*10^7-9 are all prime.

Terms

a(0) =15308a(1) =15572a(2) =22133a(3) =52499a(4) =98354a(5) =134150a(6) =135356a(7) =138422a(8) =142748a(9) =182606a(10) =223850a(11) =245111a(12) =278408a(13) =279260a(14) =322223a(15) =354608a(16) =385979a(17) =395114a(18) =404597a(19) =421070a(20) =472880a(21) =477068a(22) =491654a(23) =501092a(24) =523205a(25) =543071a(26) =549677a(27) =549989a(28) =566780a(29) =594575