A103830 a(1) = 2; a(n+1) = smallest number > a(n) whose sum of digits is a(n).

2, 11, 29, 2999

Offset: 1

Author

Zak Seidov, Feb 17 2005

Keywords

• nonn
• base

Comments

a(5) = 3*10^333-1 = 2999...999 with 333 9's and contains 334 digits.

Surprisingly enough the first four terms are all primes and match those of A062802, but a(5) is divisible by 65033 and is different from A062802(5).

Sequences with other seeds: 3,12,129,399999999999999,...; 4,13,139,4999999999999999,...; 5,14,149,59999999999999999.

Crossrefs

Differs from A062802 starting at a(5).

Formula

For n>=3, a(n) = (a(n-1) mod 9 + 1)*10^floor(a(n-1)/9) - 1. - Max Alekseyev, Aug 13 2015

For n>=3, a(n) = 3*10^b(n) - 1, where b(3)=1 and for n>=4, b(n)=(10^b(n-1)-1)/3. In other words, decimal representation of b(n) is formed by digit 3 repeated b(n-1) times. - Max Alekseyev, Aug 13 2015