Numbers n for which n' + n and n' - n are both prime, n' being the arithmetic derivative of n.

Terms

a(0) =210a(1) =330a(2) =390a(3) =690a(4) =798a(5) =966a(6) =1110a(7) =1230a(8) =2190a(9) =2310a(10) =2730a(11) =3270a(12) =4110a(13) =4530a(14) =4890a(15) =5430a(16) =6090a(17) =6270a(18) =6810a(19) =6990a(20) =7230a(21) =7890a(22) =8310a(23) =8490a(24) =9030a(25) =9210a(26) =9282a(27) =10470a(28) =10590a(29) =10770