OFFSET
1,1
COMMENTS
3318 = 2 * 3 * 7 * 79.
All terms are multiples of a(1) = 78.
For these numbers numerator(B_{n}) mod denominator(B_{n}) = 37.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000
EXAMPLE
Bernoulli B_{78} is 414846365575400828295179035549542073492199375372400483487/3318, hence 78 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, 3318);
MATHEMATICA
Select[78 Range@ 800, Denominator@ BernoulliB@ # == 3318 &] (* Michael De Vlieger, Apr 28 2016 *)
PROG
(PARI) lista(nn) = for(n=1, nn, if(denominator(bernfrac(n)) == 3318, print1(n, ", "))); \\ Altug Alkan, Apr 28 2016
(Python)
from sympy import divisors, isprime
A272383_list = []
for i in range(78, 10**6, 78):
for d in divisors(i):
if d not in (1, 2, 6, 78) and isprime(d+1):
break
else:
A272383_list.append(i) # Chai Wah Wu, May 02 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paolo P. Lava, Apr 28 2016
EXTENSIONS
a(9)-a(22) from Altug Alkan, Apr 28 2016
More terms from Michael De Vlieger, Apr 28 2016
STATUS
approved