Problimes (third definition).

Terms

a(0) =2a(1) =4a(2) =7a(3) =11a(4) =15a(5) =19a(6) =23a(7) =28a(8) =33a(9) =38a(10) =43a(11) =48a(12) =53a(13) =58a(14) =63a(15) =68a(16) =73a(17) =79a(18) =85a(19) =91a(20) =97a(21) =103a(22) =109a(23) =115a(24) =121a(25) =127a(26) =133a(27) =139a(28) =145a(29) =151