Posted by **Arnau** on Thursday, May 2, 2013 at 5:48am.

Given a positive integer n, let S(n) denote the digit sum of n. Consider the sequence of numbers given by

n₁ = S(n)

nk = S(nk−1)k≥2

For how many positive integers n ≤ 2013 does the sequence {nk} contain the number 9?

## Answer this Question

## Related Questions

- maths - Given a positive integer n, let S(n) denote the digit sum of n. Consider...
- Math - A smooth partition of the integer n is a set of positive integers a 1 ,a ...
- Math (algebra) - Suppose a and b are positive integers satisfying 1≤a&#...
- Maths - Suppose a and b are positive integers satisfying 1≤a≤31, 1&#...
- geometry - A smooth partition of the integer n is a set of positive integers a1,...
- Algebra - Let S(N) denote the digit sum of the integer N. Let M denote the ...
- math - Let S(N) denote the digit sum of the integer N. As N ranges over all 3-...
- math - Let S(N) denote the digit sum of the integer N. As N ranges over all 3-...
- Algebra - How many positive integers n≤1000 cannot be written in the form ...
- Algebra - 1) Given the arithmetic sequence an = 4 - 3(n - 1), what is the domain...