A180012 a(n) = smallest k >= 1 such that k and k*n have the same digit sum.

1, 9, 9, 3, 9, 9, 3, 9, 9, 1, 99, 9, 9, 9, 9, 9, 9, 9, 6, 9, 54, 6, 9, 9, 6, 9, 9, 4, 9, 9, 33, 36, 99, 3, 9, 9, 3, 9, 9, 3, 27, 27, 24, 99, 9, 5, 9, 9, 9, 9, 63, 6, 27, 45, 2, 9, 9, 9, 9, 9, 33, 18, 18, 5, 18, 99, 3, 9, 9, 3, 72, 45, 7, 18, 18, 15, 99, 9, 9, 9, 63, 5, 27, 18, 6, 27, 36, 15, 9, 9, 11

Offset: 1

Author

David W. Wilson, Aug 06 2010

Keywords

• base
• easy
• nonn

Examples

			For all 1 < k < 99, k and 11*k have distinct digit sum. 99 and 99*11 = 1089 have the same digit sum 18. Therefore a(11) = 99.
		

Links

• D. W. Wilson, Table of n, a(n) for n=1..10000