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 A355658 Smallest prime base q such that q^(p-1) == 1 (mod p^2), where p = prime(n). 0
 5, 17, 7, 19, 3, 19, 131, 127, 263, 41, 229, 691, 313, 19, 53, 521, 53, 601, 1301, 11, 619, 31, 269, 3187, 53, 181, 43, 317, 499, 373, 911, 659, 19, 3659, 313, 751, 233, 4373, 3307, 419, 2591, 313, 1249, 2897, 349, 709, 331, 1973, 1933, 503, 821, 977, 2371, 263 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) differs from A125636(n) if and only if p is a Wieferich prime (A001220). In particular, a(183) = 2 and A125636(183) = 18979. Similarly, a(490) = 2 and A125636(490) = 82183. LINKS Table of n, a(n) for n=1..54. PROG (PARI) a(n) = my(p=prime(n)); forprime(q=1, , if(Mod(q, p^2)^(p-1)==1, return(q))) CROSSREFS Cf. A001220, A125636, A039678. Sequence in context: A170866 A337031 A125636 * A156323 A286816 A276831 Adjacent sequences: A355655 A355656 A355657 * A355659 A355660 A355661 KEYWORD nonn AUTHOR Felix Fröhlich, Jul 12 2022 STATUS approved

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Last modified May 28 16:59 EDT 2023. Contains 363019 sequences. (Running on oeis4.)