Congruent to 0 or 1 mod 5.

Terms

a(0) =0a(1) =1a(2) =5a(3) =6a(4) =10a(5) =11a(6) =15a(7) =16a(8) =20a(9) =21a(10) =25a(11) =26a(12) =30a(13) =31a(14) =35a(15) =36a(16) =40a(17) =41a(18) =45a(19) =46a(20) =50a(21) =51a(22) =55a(23) =56a(24) =60a(25) =61a(26) =65a(27) =66a(28) =70a(29) =71