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A077806
Greatest prime factor of numbers containing in their decimal representation only the digits 0 and 1.
2
1, 5, 11, 5, 101, 11, 37, 5, 13, 101, 337, 11, 367, 37, 101, 5, 137, 13, 71, 101, 37, 337, 10111, 11, 193, 367, 13, 37, 653, 101, 271, 5, 9091, 137, 53, 13, 547, 71, 479, 101, 257, 37, 1217, 337, 101, 10111, 101111, 11, 991, 193, 137, 367, 4787, 13, 739, 37
OFFSET
1,2
FORMULA
a(n) = A006530(A007088(n)).
EXAMPLE
a(45) = A006530(A007088(45)) = A006530(101101) = A006530(7*11*13*101) = 101.
MATHEMATICA
FactorInteger[#][[-1, 1]]&/@Rest[FromDigits/@Tuples[{0, 1}, 6]] (* Harvey P. Dale, Feb 07 2015 *)
CROSSREFS
Sequence in context: A110353 A377050 A097720 * A365731 A019305 A274266
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Nov 16 2002
STATUS
approved