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 A122271 a(n) is the smallest prime whose cube divides the numerator of the Bernoulli number B(A122270(n)). 5
 5, 7, 5, 5, 7, 5, 5, 11, 7, 5, 5, 7, 5, 5, 13, 5, 7, 5, 7, 5, 5, 5, 7, 5, 7, 5, 11, 5, 5, 13, 7, 5, 7, 5, 17 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS The Bernoulli Number Page, Table of factors of the numerators of Bernoulli numbers Bn in the range n = 2..10000, 2018. S. S. Wagstaff, Jr, Prime factors of the absolute values of Bernoulli numerators, 2018. EXAMPLE a(1) = 5 because 5^3 divides numerator(B(A122270(1)) = numerator(B(250)), but 3^3 does not. CROSSREFS Cf. A000367, A090997, A090987, A122270, A122272, A122273. Sequence in context: A161376 A107437 A317083 * A011205 A167133 A144567 Adjacent sequences:  A122268 A122269 A122270 * A122272 A122273 A122274 KEYWORD nonn,more AUTHOR Alexander Adamchuk, Aug 28 2006 EXTENSIONS Various sections edited by Petros Hadjicostas, May 12 2020 STATUS approved

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Last modified September 18 22:25 EDT 2020. Contains 337174 sequences. (Running on oeis4.)