Periods of sum of 8th powers of digits iterated until the sequence becomes periodic.

Terms

a(0) =1a(1) =1a(2) =25a(3) =154a(4) =154a(5) =154a(6) =154a(7) =25a(8) =154a(9) =154a(10) =1a(11) =25a(12) =154a(13) =154a(14) =1a(15) =25a(16) =25a(17) =1a(18) =154a(19) =154a(20) =25a(21) =154a(22) =154a(23) =25a(24) =154a(25) =154a(26) =154a(27) =25a(28) =154a(29) =1