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 A305333 Let p be the n-th base-5 Wieferich prime (A123692). a(n) is the value of p-1 divided by the multiplicative order of 5 (mod p^2). 2
 1, 2, 1, 4, 1, 1, 16 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..7. FORMULA a(n) = (A123692(n)-1)/A305332(n). PROG (PARI) v=[2, 20771, 40487, 53471161, 1645333507, 6692367337, 188748146801]; for(k=1, #v, my(ord=znorder(Mod(5, v[k]^2))); print1((v[k]-1)/ord, ", ")) CROSSREFS Cf. A123692, A211241, A305331, A305332. Sequence in context: A068009 A140168 A059119 * A127772 A086256 A227964 Adjacent sequences: A305330 A305331 A305332 * A305334 A305335 A305336 KEYWORD nonn,hard,more AUTHOR Felix Fröhlich, May 30 2018 STATUS approved

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Last modified August 14 15:53 EDT 2024. Contains 375165 sequences. (Running on oeis4.)