a(n) = 12*n + 6.

Terms

a(0) =6a(1) =18a(2) =30a(3) =42a(4) =54a(5) =66a(6) =78a(7) =90a(8) =102a(9) =114a(10) =126a(11) =138a(12) =150a(13) =162a(14) =174a(15) =186a(16) =198a(17) =210a(18) =222a(19) =234a(20) =246a(21) =258a(22) =270a(23) =282a(24) =294a(25) =306a(26) =318a(27) =330a(28) =342a(29) =354