a(n)=2a(n-1) but when sum of digits of 2a(n-1) is greater than 9 take a(n) = largest number < 2a(n-1) which has sum of digits = 9.
A140134
a(n)=2a(n-1) but when sum of digits of 2a(n-1) is greater than 9 take a(n) = largest number < 2a(n-1) which has sum of digits = 9.
Terms
- a(0) =1a(1) =2a(2) =4a(3) =8a(4) =16a(5) =32a(6) =63a(7) =126a(8) =252a(9) =504a(10) =1008a(11) =2016a(12) =4032a(13) =8001a(14) =16002a(15) =32004a(16) =63000a(17) =126000a(18) =252000a(19) =504000a(20) =1008000a(21) =2016000a(22) =4032000a(23) =8001000a(24) =16002000a(25) =32004000a(26) =63000000a(27) =126000000a(28) =252000000a(29) =504000000
External references
- oeis: A140134