Bemirps that also interpret 2 and 5 as upside-down forms of each other, assuming a digital font.

Terms

a(0) =1061a(1) =1091a(2) =1601a(3) =1901a(4) =10061a(5) =10091a(6) =16001a(7) =19001a(8) =106861a(9) =109891a(10) =110651a(11) =110921a(12) =120121a(13) =121021a(14) =121921a(15) =129011a(16) =129121a(17) =150151a(18) =151051a(19) =151651a(20) =156011a(21) =156151a(22) =168601a(23) =198901a(24) =1022591a(25) =1026521a(26) =1028011a(27) =1055261a(28) =1058011a(29) =1059251