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A282773
Numbers n such that Bernoulli number B_{n} has denominator 498.
15
82, 574, 1066, 1394, 3034, 3362, 3854, 4838, 5494, 5822, 6478, 7462, 7954, 8282, 8774, 8938, 10414, 11234, 12218, 12382, 12874, 13694, 15826, 16154, 17302, 18614, 18778, 21074, 21238, 21566, 22058, 22222, 22714, 23206, 23534, 23698, 25174, 25502, 25994
OFFSET
1,1
COMMENTS
498 = 2 * 3 * 83.
All terms are multiples of a(1) = 82.
For these numbers numerator(B_{n}) mod denominator(B_{n}) = 77.
n such that 82 | n but there are no primes p other than 2, 3, 83 such that p-1 | n. - Robert Israel, Mar 07 2017
EXAMPLE
Bernoulli B_{82} is 1677014149185145836823154509786269900207736027570253414881613/498, hence 82 is in the sequence.
MAPLE
with(numtheory): P:=proc(q, h) local n; for n from 2 by 2 to q do
if denom(bernoulli(n))=h then print(n); fi; od; end: P(10^6, 498);
# Alternative:
filter:= n ->
select(isprime, map(`+`, numtheory:-divisors(n), 1)) = {2, 3, 83}:
select(filter, [seq(i, i=82..10^5, 82)]); # Robert Israel, Mar 07 2017
MATHEMATICA
Select[82 Range[360], Denominator@ BernoulliB@ # == 498 &] (* Michael De Vlieger, Mar 07 2017 *)
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Mar 07 2017
EXTENSIONS
More terms from Michael De Vlieger, Mar 07 2017
STATUS
approved