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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Index entries for sequences related to pseudoprimes

FORMULA

a(n) = A020639(A001262(n)).

EXAMPLE

The 8th pseudoprime, 42799, is divisible by 127.

CROSSREFS

Sequence in context: A153631 A082943 A061754 * A101784 A101802 A156983

Adjacent sequences:  A180063 A180064 A180065 * A180067 A180068 A180069

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

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Last modified July 18 19:00 EDT 2019. Contains 325144 sequences. (Running on oeis4.)