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A295593
Numbers k such that Bernoulli number B_{k} has denominator 230010.
1
80, 160, 320, 13360, 17840, 18160, 20560, 25360, 26720, 28240, 30640, 35680, 36320, 36560, 41120, 43280, 45520, 46960, 50720, 52880, 56480, 60080, 61280, 69040, 70960, 71360, 72560, 72640, 79280, 84080, 87760, 91040, 92240, 93040, 93680, 93920, 94480, 97040, 97360
OFFSET
1,1
COMMENTS
230010 = 2*3*5*11*17*41.
All terms are multiples of a(1) = 80.
For these numbers numerator(B_{k}) mod denominator(B_{k}) = 182293.
LINKS
EXAMPLE
Bernoulli B_{80} is
-4603784299479457646935574969019046849794257872751288919656867/230010, hence 80 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, 230010);
# Alternative: # according to Robert Israel code in A282773
with(numtheory): filter:= n ->
select(isprime, map(`+`, divisors(n), 1)) = {2, 3, 5, 11, 17, 41}:
select(filter, [seq(i, i=1..10^5)]);
KEYWORD
nonn,easy
AUTHOR
Paolo P. Lava, Nov 24 2017
STATUS
approved