Numbers k such that k-th semiprime == 1 (mod k).

Terms

a(0) =1a(1) =27a(2) =28a(3) =35a(4) =40a(5) =44a(6) =47a(7) =55a(8) =56a(9) =72a(10) =613400a(11) =613401a(12) =613457a(13) =613482a(14) =613530a(15) =613538a(16) =613544a(17) =613550a(18) =613554a(19) =613556a(20) =613560a(21) =613614a(22) =58155520a(23) =58155521a(24) =58155533a(25) =58155537a(26) =58155540a(27) =58155543a(28) =58155545a(29) =58155571