Numbers k such that the k-th semiprime == 4 (mod k).

Terms

a(0) =1a(1) =2a(2) =5a(3) =37a(4) =38a(5) =58a(6) =61a(7) =70a(8) =77a(9) =613379a(10) =613413a(11) =613415a(12) =613429a(13) =613485a(14) =613509a(15) =613518a(16) =613521a(17) =613533a(18) =613543a(19) =613599a(20) =6384425449a(21) =6384425459a(22) =6384425463a(23) =6384425517a(24) =6384425557a(25) =6384425574a(26) =6384425634