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A087020
Greatest prime factor of n-th cyclic number.
6
37, 5882353, 333667, 513239, 121499449, 11111111111111111111111, 154083204930662557781201849, 39526741, 9999999900000001, 59779577156334533866654838281, 119968369144846370226083377, 8396862596258693901610602298557167100076327481
OFFSET
1,1
COMMENTS
A004042(n) factorized with Dario Alpern's ECM.
Extended using factors of 10^(A001913(n)-1)-1, see Kamada link.
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..51 (first 42 terms from Ray Chandler)
Eric Weisstein's World of Mathematics, Cyclic Number
FORMULA
a(n) = A006530(A004042(n+1)).
EXAMPLE
A004042(2) = 142857 = 37*13*11*3^3, therefore a(1) = 37.
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 30 2003
EXTENSIONS
a(12) from Ray Chandler, Nov 16 2011
STATUS
approved