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A087001 Left half of periodic part of decimal expansion of 1/p for those primes having a periodic part of even length. 4
142, 9, 769, 58823529, 526315789, 43478260869, 34482758620689, 21276595744680851063829, 16949152542372881355932203389, 163934426229508196721311475409, 1369, 1123595505617977528089 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = floor(A086999(n)/10^A087000(n)); A055642(a(n))=A087000(n);

a(n) + A087002(n) = 10^A087000(n) - 1.

REFERENCES

H. Rademacher and O. Toeplitz, Von Zahlen und Figuren (Springer 1930, reprinted 1968), ch. 19, Die periodischen Dezimalbrueche.

LINKS

Table of n, a(n) for n=1..12.

Eric Weisstein's World of Mathematics, Midy's Theorem

Index entries for sequences related to decimal expansion of 1/n.

EXAMPLE

p=17: A086999(4)=5882352941176470 -> [58823529][41176470] ->

A087001(4)=58823529, A087002(4)=41176470,

A087001(4)+A087002(4)=58823529+41176470=99999999.

CROSSREFS

Sequence in context: A172668 A172764 A172836 * A025379 A202279 A035702

Adjacent sequences:  A086998 A086999 A087000 * A087002 A087003 A087004

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Jul 29 2003

STATUS

approved

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Last modified December 16 08:42 EST 2018. Contains 318158 sequences. (Running on oeis4.)