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Smallest number such that the sum of the digits of n * a(n) is greater than n.
2

%I #16 Jul 26 2022 01:36:23

%S 2,2,2,2,3,3,4,6,11,29,6,8,6,7,33,18,17,111,21,249,38,44,39,162,239,

%T 153,737,246,231,2333,258,309,303,882,1971,8333,2027,1842,2051,19997,

%U 2439,7119,2093,13409,111111,13043,10617,20831,18161,399999,72549,55769,56583

%N Smallest number such that the sum of the digits of n * a(n) is greater than n.

%F a(n) = A269332(n) / n.

%o (PARI) a(n) = my(m=2*n); while (sumdigits(m) <= n, m+=n); m/n; \\ _Michel Marcus_, Feb 24 2016

%o (Python)

%o from itertools import count

%o def A269333(n): return next(k for k in count(2) if sum(map(int,str(k*n)))>n) # _Chai Wah Wu_, Jul 25 2022

%Y Cf. A269332.

%K nonn,base

%O 1,1

%A _Franklin T. Adams-Watters_, Feb 24 2016

%E More terms from _Michel Marcus_, Feb 24 2016