A095156 Least k such that 1/k begins with n after deleting the decimal point and the zeros following the decimal point.

6, 4, 3, 21, 2, 15, 13, 12, 11, 10, 9, 8, 72, 7, 63, 6, 56, 53, 51, 5, 46, 44, 42, 41, 4, 38, 36, 35, 34, 33, 32, 31, 3, 29, 28, 271, 27, 26, 251, 25, 24, 233, 23, 223, 22, 213, 21, 205, 201, 2, 193, 19, 186, 182, 18, 176, 173, 17, 167, 164, 162, 16, 157, 154, 152, 15, 148

Offset: 1

Author

Amarnath Murthy, May 31 2004

Keywords

• base
• nonn

Examples

			a(1) =  6 -> 1/6 = 0.{1}666666...
a(2) =  4 -> 1/4 = 0.{2}500000...
a(3) =  3 -> 1/3 = 0.{3}333333...
a(4) = 21 -> 1/4 = 0.0{4}76190...
a(5) =  2 -> 1/2 = 0.{5}000000...
a(7) = 13 as 1/13 = 0.0767... and on deleting the decimal point one gets 0714... = 714... which begins with 7.
a(8) = 12 though 1/125 = 0.8. 1/12 = 0.083...
		

Links

• Paul Tek, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A034057.

Programs

Mathematica

Do[k = 1; l = {}; d = IntegerDigits[n]; While[FromDigits[l] != n, k++; f = First[RealDigits[N[1/k, 10]]]; If[Length[f] > Length[d], l = Take[f, Length[d]], l = f]]; Print[k], {n, 1, 100}] (* Ryan Propper, Aug 10 2005 *)

Extensions

Corrected and extended by Ryan Propper, Aug 10 2005

Edited by N. J. A. Sloane, May 07 2007