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 A339536 Numbers b > 1 such that the smallest seven primes, i.e., 2, 3, 5, 7, 11, 13 and 17 are base-b Wieferich primes. 6
 4486949, 4651993, 4941649, 5571593, 11903257, 19397501, 19841257, 19942001, 20610901, 21530501, 25793893, 42969601, 44404093, 46336949, 51509701, 52786493, 53740457, 54561401, 56120257, 56904857, 63789749, 64028593, 65497301, 65666449, 68441957, 72582101 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS PROG (PARI) is(n) = forprime(p=1, 17, if(Mod(n, p^2)^(p-1)!=1, return(0))); 1 CROSSREFS Cf. A256236. Row 1 of A319064. Cf. smallest k primes are base-b Wieferich primes: A339531 (k=2), A339532 (k=3), A339533 (k=4), A339534 (k=5), A339535 (k=6), A339537 (k=8). Sequence in context: A244575 A105649 A015337 * A319064 A344831 A183679 Adjacent sequences:  A339533 A339534 A339535 * A339537 A339538 A339539 KEYWORD nonn AUTHOR Felix Fröhlich, Dec 08 2020 STATUS approved

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Last modified December 2 05:01 EST 2021. Contains 349437 sequences. (Running on oeis4.)