Numbers with digits 2 and 9 only.

Terms

a(0) =2a(1) =9a(2) =22a(3) =29a(4) =92a(5) =99a(6) =222a(7) =229a(8) =292a(9) =299a(10) =922a(11) =929a(12) =992a(13) =999a(14) =2222a(15) =2229a(16) =2292a(17) =2299a(18) =2922a(19) =2929a(20) =2992a(21) =2999a(22) =9222a(23) =9229a(24) =9292a(25) =9299a(26) =9922a(27) =9929a(28) =9992a(29) =9999