Primes having only {5, 6, 7, 8} as digits.

Terms

a(0) =5a(1) =7a(2) =67a(3) =557a(4) =577a(5) =587a(6) =677a(7) =757a(8) =787a(9) =857a(10) =877a(11) =887a(12) =5557a(13) =5657a(14) =5857a(15) =5867a(16) =6577a(17) =6857a(18) =7577a(19) =7687a(20) =7757a(21) =7867a(22) =7877a(23) =8677a(24) =8867a(25) =8887a(26) =55667a(27) =55787a(28) =56687a(29) =56767