Numbers k such that phi(k) + prime(k) is a triangular number.

Terms

a(0) =1a(1) =5a(2) =6a(3) =15a(4) =23a(5) =141a(6) =150a(7) =258a(8) =317a(9) =340a(10) =359a(11) =378a(12) =471a(13) =503a(14) =768a(15) =1363a(16) =2175a(17) =2516a(18) =3285a(19) =3342a(20) =3815a(21) =3905a(22) =4385a(23) =4748a(24) =5385a(25) =5976a(26) =6026a(27) =6900a(28) =7048a(29) =7151