Primes which can be expressed as concatenation of powers of 5 and 0's.

Terms

a(0) =5a(1) =11a(2) =101a(3) =151a(4) =251a(5) =1051a(6) =1151a(7) =1511a(8) =2551a(9) =5011a(10) =5051a(11) =5101a(12) =5501a(13) =10111a(14) =10151a(15) =10501a(16) =11251a(17) =11551a(18) =12511a(19) =15101a(20) =15511a(21) =15551a(22) =25111a(23) =50051a(24) =50101a(25) =50111a(26) =50551a(27) =51001a(28) =51151a(29) =51511