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%I #23 Sep 08 2022 08:45:23
%S 14,26,38,62,74,86,122,134,146,158,194,206,218,254,278,302,314,326,
%T 362,386,398,422,446,458,482,542,554,566,614,626,662,674,698,734,746,
%U 758,794,818,842,866,878,914,926,974,998,1046,1082,1094,1142,1154,1202,1214
%N Semiprimes of the form 6n+2.
%C {6} + A112772 + A112774 = A100484 = 2*A000040.
%C Rado showed that for a given Bernoulli number B_n there exist infinitely many Bernoulli numbers B_m having the same denominator. As a special case, if n = 2p where p is an odd prime p == 1 (mod 3), then the denominator of the Bernoulli number B_n equals 6. - _Bernd C. Kellner_, Mar 21 2018
%H Harvey P. Dale, <a href="/A112772/b112772.txt">Table of n, a(n) for n = 1..1000</a>
%H R. Rado, <a href="http://dx.doi.org/10.1112/jlms/s1-9.2.88">A note on the Bernoullian numbers</a>, J. London Math. Soc. 9 (1934) 88-90.
%F a(n) = 2 * A002476(n) = 6 * A024892(n) + 2.
%F denominator(Bernoulli(a(n)) = 6. - _Bernd C. Kellner_, Mar 21 2018
%t Select[6Range[0,300]+2,PrimeOmega[#]==2&] (* _Harvey P. Dale_, Oct 04 2011 *)
%o (Magma) IsSemiprime:= func<n | &+[d[2]: d in Factorization(n)] eq 2>; [s: n in [0..210] | IsSemiprime(s) where s is 6*n + 2]; // _Vincenzo Librandi_, Sep 22 2012
%o (PARI) 2*select(n->n%3==1,primes(100)) \\ _Charles R Greathouse IV_, Sep 22 2012
%Y Subsequence of A051222. - _Bernd C. Kellner_, Mar 21 2018
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_ and _Ray Chandler_, Oct 15 2005
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