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Integers n such that (sum of digits of 10234*n) = n.
0

%I #19 Sep 24 2013 02:56:43

%S 10,13,15,18,20,21,22,23,24,25,26,27,28,32,34,37,38

%N Integers n such that (sum of digits of 10234*n) = n.

%C Inspired by Carmine Suriano's comment in A113315.

%C Proof that 38 is the highest value: 10234*38=388892 has 6 digits. Maximum value of digitsum for a 6-digit numer is 54. Direct inspection of digitsum of 10234*39=399126 through 10234*54=552637 shows that no other solution exists. For numbers 55 through 97, direct inspection shows that no other solution exists either. For n>97, the number has 7 digits, having 63 as its maximum digitsum; therefore, no solution exists for any number >97. - _Carmine Suriano_, Sep 23 2013

%e A007953(10234*n) = n.

%Y Cf. A005349, A007953, A113315.

%K base,nonn,fini,full

%O 1,1

%A _Zak Seidov_, May 23 2013