Monotonic ordering of nonnegative differences 10^i-4^j, for 40>=i>=0, j>=0.

Terms

a(0) =0a(1) =6a(2) =9a(3) =36a(4) =84a(5) =96a(6) =99a(7) =744a(8) =936a(9) =984a(10) =996a(11) =999a(12) =5904a(13) =8976a(14) =9744a(15) =9936a(16) =9984a(17) =9996a(18) =9999a(19) =34464a(20) =83616a(21) =95904a(22) =98976a(23) =99744a(24) =99936a(25) =99984a(26) =99996a(27) =99999a(28) =737856a(29) =934464