0,3

The base 9/5 expansion is unique, and thus the sum of digits function is well-defined.

Table of n, a(n) for n=0..67.

In base 9/5 the number 11 is represented by 52 and so a(11) = 5 + 2 = 7.

(Sage)

def base95sum(n):

....L=[n]

....i=1

....while L[i-1]>=9:

........x=L[i-1]

........L[i-1]=x.mod(9)

........L.append(5*floor(x/9))

........i+=1

....return sum(L)

[base95sum(y) for y in [0..200]]

Cf. A024653, A053830, A007953.

Sequence in context: A282779 A305902 A245350 * A097377 A234741 A063917

Adjacent sequences: A245351 A245352 A245353 * A245355 A245356 A245357

nonn,base

James Van Alstine, Jul 18 2014

approved