This site is supported by donations to The OEIS Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A178505 Decimal form of the period of 1/n for n such that gcd(n,10)=1. Leading zeros are suppressed. 5
 3, 142857, 1, 9, 76923, 588235294117647, 52631578947368421, 47619, 434782608695652173913, 37, 344827586206896551724137931, 32258064516129, 3, 27, 25641, 2439, 23255813953488372093 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The numbers n are A045572, and the corresponding periods are A002329. LINKS Ray Chandler, Table of n, a(n) for n = 1..406 (terms up to 1000 digits) FORMULA a(n) = A060284(A045572(n+1)). [R. J. Mathar, Jun 26 2010] EXAMPLE 3 is in the sequence because 1/3 = 0.3333... 142857 is in the sequence because 1/7 = 0.142857 142857 ... 1 is in the sequence because 1/9 = 0.1111.... MAPLE with(numtheory): nn:= 100: T:=array(1..nn):k:=1: U:=array(1..nn):k:=1: for n from 2 to 200 do:x:=1/n:for p from 1 to 200 while(irem(10^p, n)<>1 or gcd(n, 10)<> 1) do:od: if irem(10^p, n) = 1 and gcd(n, 10) = 1 then y:=floor(x*10^p): T[k]:=y: U[k]:=n : k:=k+1:else fi:od:print(T): CROSSREFS Cf. A002329, A036275, A045572, A060284. Sequence in context: A159577 A116536 A224241 * A306594 A003544 A250495 Adjacent sequences:  A178502 A178503 A178504 * A178506 A178507 A178508 KEYWORD nonn,base AUTHOR Michel Lagneau, May 29 2010 EXTENSIONS Name corrected by T. D. Noe, Jul 07 2010 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 24 21:16 EDT 2019. Contains 324337 sequences. (Running on oeis4.)