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Numbers k such that Bernoulli number B_{k} has denominator 230010.
1

%I #10 Dec 09 2017 20:26:05

%S 80,160,320,13360,17840,18160,20560,25360,26720,28240,30640,35680,

%T 36320,36560,41120,43280,45520,46960,50720,52880,56480,60080,61280,

%U 69040,70960,71360,72560,72640,79280,84080,87760,91040,92240,93040,93680,93920,94480,97040,97360

%N Numbers k such that Bernoulli number B_{k} has denominator 230010.

%C 230010 = 2*3*5*11*17*41.

%C All terms are multiples of a(1) = 80.

%C For these numbers numerator(B_{k}) mod denominator(B_{k}) = 182293.

%H Seiichi Manyama, <a href="/A295593/b295593.txt">Table of n, a(n) for n = 1..1000</a>

%e Bernoulli B_{80} is

%e -4603784299479457646935574969019046849794257872751288919656867/230010, hence 80 is in the sequence.

%p with(numtheory): P:=proc(q, h) local n; for n from 2 by 2 to q do

%p if denom(bernoulli(n))=h then print(n); fi; od; end: P(10^6,230010);

%p # Alternative: # according to Robert Israel code in A282773

%p with(numtheory): filter:= n ->

%p select(isprime, map(`+`, divisors(n), 1)) = {2, 3, 5, 11, 17, 41}:

%p select(filter, [seq(i, i=1..10^5)]);

%Y Cf. A045979, A051222, A051225, A051226, A051227, A051228, A051229, A051230, A119456, A119480, A249134, A255684, A271634, A271635, A272138, A272139, A272140, A272183, A272184, A272185, A272186, A272369.

%K nonn,easy

%O 1,1

%A _Paolo P. Lava_, Nov 24 2017