|
|
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).
|
|
0
|
|
|
3, 61, 175, 571, 2414, 4142, 9011, 359772, 86249511, 535238681, 124396878308, 803878693421, 6126660122361, 13506262793047, 74039726260531, 76729882123723031, 655537561065645251, 882122044899263311
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
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
|
|
|
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
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
Gil Broussar (kikiriki(AT)mindspring.com), Apr 08 2005
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|