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A051226 Bernoulli number B_{n} has denominator 30. 28
4, 8, 68, 76, 124, 152, 188, 236, 244, 248, 284, 376, 404, 412, 428, 436, 472, 488, 548, 596, 604, 628, 668, 724, 788, 824, 844, 872, 892, 908, 916, 964, 1028, 1052, 1076, 1084, 1132, 1156, 1208, 1244, 1252, 1256, 1268, 1324, 1336, 1348, 1388 (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.

Numbers n such that numerator(B_{n}) mod denominator(B_{n}) = 29. - Paolo P. Lava, Mar 30 2015

REFERENCES

B. C. Berndt, Ramanujan's Notebooks Part IV, Springer-Verlag, see p. 75.

G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 5th ed., Oxford Univ. Press, 1979, Th. 118.

H. Rademacher, Topics in Analytic Number Theory, Springer, 1973, Chap. 1.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to Bernoulli numbers.

MATHEMATICA

Select[Table[n, {n, 4, 1500, 2}], Denominator @ BernoulliB[#] == 30 &] [[1 ;; 47]] (* Jean-Fran├žois Alcover, Apr 08 2011 *)

PROG

(Perl) @p=(2, 3, 5); $p=5; for($n=4; $n<=1388; $n+=4){while($p<$n+1){$p+=2; next if grep$p%$_==0, @p; push@p, $p; push@c, $p-1; }print"$n, "if!grep$n%$_==0, @c; }print"\n"

(PARI) lista(nn) = for (n=1, nn, if (denominator(bernfrac(n)) == 30, print1(n, ", "))); \\ Michel Marcus, Mar 30 2015

CROSSREFS

Cf. A045979, A051222, A051225, A051227, A051228, A051229, A051230.

Sequence in context: A117636 A285634 A228930 * A013112 A274461 A206346

Adjacent sequences:  A051223 A051224 A051225 * A051227 A051228 A051229

KEYWORD

nonn,nice,easy

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms and Perl program from Hugo van der Sanden

STATUS

approved

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Last modified March 21 12:09 EDT 2019. Contains 321369 sequences. (Running on oeis4.)