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A180066
Smallest prime factor of 2-strong pseudoprimes.
1
23, 29, 37, 31, 53, 7, 13, 127, 157, 7, 97, 5, 61, 53, 149, 151, 229, 137, 157, 103, 43, 41, 157, 233, 151, 277, 13, 131, 313, 277, 11, 233, 157, 359, 499, 13, 79, 431, 5, 101, 397, 661, 307, 479, 313, 331, 13, 251, 11, 601, 103, 1093, 449, 409, 733, 571, 499, 673, 829
OFFSET
1,1
FORMULA
a(n) = A020639(A001262(n)).
EXAMPLE
The 8th pseudoprime, 42799, is divisible by 127.
CROSSREFS
Sequence in context: A082943 A061754 A375595 * A353286 A101784 A101802
KEYWORD
nonn
AUTHOR
Kevin Batista (kevin762401(AT)yahoo.com), Aug 09 2010
EXTENSIONS
b-file and edits from Charles R Greathouse IV, Aug 28 2010
STATUS
approved