a(n+1) = a(n) + sum of digits in base 4 representation of a(n), with a(0) = 1.

Terms

a(0) =1a(1) =2a(2) =4a(3) =5a(4) =7a(5) =11a(6) =16a(7) =17a(8) =19a(9) =23a(10) =28a(11) =32a(12) =34a(13) =38a(14) =43a(15) =50a(16) =55a(17) =62a(18) =70a(19) =74a(20) =79a(21) =86a(22) =91a(23) =98a(24) =103a(25) =110a(26) =118a(27) =125a(28) =133a(29) =137