A069860 Numbers n that divide the concatenation of n+1 and n+2.
1, 2, 3, 4, 6, 17, 34, 51, 167, 334, 501, 1667, 3334, 5001, 14286, 16667, 33334, 50001, 166667, 333334, 500001, 1666667, 3333334, 5000001, 16666667, 33333334, 50000001, 166666667, 333333334, 500000001, 1666666667, 3333333334
Offset: 1
Examples
17 divides 1819 hence is a member.
Programs
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Mathematica
Select[ Range[10^7], Mod[ FromDigits[ Join[ IntegerDigits[ # + 1], IntegerDigits[ # + 2]]], # ] == 0 & ]
Formula
For k > 0, sequence contains (10^k+2)/2, (10^k+2)/3, (10^k+2)/6 and (10^(6k-1)+2)/7. The only other terms are 1 and 3. - David Wasserman, Aug 25 2005
Extensions
Edited and extended by Robert G. Wilson v, Apr 22 2002
More terms from David Wasserman, Aug 25 2005