A105430 - OEIS

A105430

Numbers n such that reciprocal of n contains the reverse of n as a string of digits to the immediate right of the decimal point (excluding leading zeros).

3, 61, 175, 571, 2414, 4142, 9011, 359772, 86249511, 535238681, 124396878308, 803878693421, 6126660122361, 13506262793047, 74039726260531, 76729882123723031, 655537561065645251, 882122044899263311

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OFFSET

1,1

COMMENTS

n for which 10^(2k-1)-n < n*reverse(n) <= 10^(2k-1), where k is the length of n. - Max Alekseyev, Apr 11 2005

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

a(3)=175 because 1/175 = 0.005714285...

MATHEMATICA

fQ[n_] := Block[{lg = Floor[ Log[10, n] + 1]}, IntegerDigits[n] == Reverse[ Take[ RealDigits[1/n, 10, 24][[1]], lg]]]; lst = {}; Do[ If[ fQ[n], AppendTo[lst, n]], {n, 2, 10^7}]; lst (* Robert G. Wilson v, Apr 09 2005 *)

CROSSREFS

Cf. A074841, A105429.

Sequence in context: A106883 A037209 A181505 * A141979 A185831 A301666

Adjacent sequences: A105427 A105428 A105429 * A105431 A105432 A105433

KEYWORD

nonn,base

AUTHOR

Gil Broussar (kikiriki(AT)mindspring.com), Apr 08 2005

EXTENSIONS

More terms from Max Alekseyev, Apr 11 2005

Further terms from Max Alekseyev, Apr 29 2005

STATUS

approved