a(n) = x is the smallest number such that gcd(prime(x)+1, x) = n.

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =35a(5) =24a(6) =63a(7) =56a(8) =45a(9) =10a(10) =649a(11) =132a(12) =91a(13) =42a(14) =495a(15) =48a(16) =153a(17) =54a(18) =779a(19) =700a(20) =1785a(21) =264a(22) =851a(23) =96a(24) =1125a(25) =286a(26) =1647a(27) =672a(28) =551a(29) =570