Near-repdigit semiprimes with 7 as repeated digit.

Terms

a(0) =177a(1) =377a(2) =707a(3) =717a(4) =737a(5) =767a(6) =771a(7) =778a(8) =779a(9) =3777a(10) =4777a(11) =5777a(12) =7277a(13) =7377a(14) =7737a(15) =7747a(16) =7771a(17) =7773a(18) =7778a(19) =7779a(20) =7787a(21) =7977a(22) =8777a(23) =9777a(24) =17777a(25) =37777a(26) =57777a(27) =70777a(28) =77177a(29) =77277