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 A051229 Bernoulli number B_{2n} has denominator 66. 33
 5, 25, 85, 185, 235, 295, 305, 335, 355, 365, 395, 425, 505, 535, 635, 685, 695, 745, 815, 835, 925, 985, 995, 1115, 1135, 1145, 1285, 1315, 1345, 1385, 1415, 1445, 1475, 1525, 1535, 1555, 1565, 1585, 1655, 1675, 1735, 1765 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS From the Von Staudt-Clausen theorem, denominator(B_2n) = product of primes p such that (p-1)|2n. REFERENCES B. C. Berndt, Ramanujan's Notebooks Part IV, Springer-Verlag, see p. 75. LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Range[2000], Denominator[BernoulliB[2 #]]==66&] (* Harvey P. Dale, Mar 11 2012 *) PROG (PARI) is(n)=denominator(bernfrac(2*n))==66 \\ Charles R Greathouse IV, Feb 06 2017 CROSSREFS Cf. A045979, A051222, A051225-A051230. Equals A051230/2. Sequence in context: A131537 A250555 A147122 * A058919 A018212 A181477 Adjacent sequences:  A051226 A051227 A051228 * A051230 A051231 A051232 KEYWORD nonn,nice,easy AUTHOR EXTENSIONS More terms from Michael Somos STATUS approved

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Last modified January 18 06:34 EST 2019. Contains 319269 sequences. (Running on oeis4.)