A075016 Smallest k such that the concatenation k, k-1,k-2 is divisible by n; or 0 if no such number exists.

2, 2, 2, 4, 2, 2, 2, 4, 4, 2, 12, 4, 105, 2, 2, 4, 7, 4, 18, 22, 2, 12, 11, 4, 27, 118, 4, 106, 21, 2, 23, 14, 12, 34, 2, 4, 112, 18, 105, 22, 15, 2, 39, 34, 7, 14, 9, 4, 141, 52, 7, 118, 58, 4, 12, 106, 18, 50, 38, 22, 10, 54, 106, 14, 157

Offset: 1

Author

Amarnath Murthy, Sep 01 2002

Keywords

• base
• nonn

Examples

			a(11) = 12 as 11 divides 121110.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A075113, A075114, A075115, A075117.

Programs

Mathematica

skc[n_]:=Module[{k=2},While[Mod[FromDigits[Flatten[IntegerDigits/@ Range[ k,k-2,-1]]],n]!=0,k++];k]; Array[skc,70] (* Harvey P. Dale, Nov 01 2019 *)

Extensions

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 19 2003