%I #18 Sep 16 2020 07:37:15
%S 1,18,810,10206,65610,1299078,483611310,9565938,7317942570,
%T 103053850074,383546284110,1443528742014,257010878197710,
%U 5083731656658,6634269811938690,982924264619854326,315013432104812970
%N Denominator of Bernoulli(2n,1/3).
%H <a href="/index/Be#Bernoulli">Index entries for sequences related to Bernoulli numbers.</a>
%p with(numtheory): seq(denom(bernoulli(2*n, 1/3)), n=0..20);
%t Denominator/@BernoulliB[2Range[0,20],1/3] (* _Harvey P. Dale_, May 11 2011 *)
%o (PARI) a(n) = denominator(subst(bernpol(2*n), x, 1/3)); \\ _Michel Marcus_, Sep 16 2020
%Y Cf. A033470 (numerators).
%K nonn,frac
%O 0,2
%A _N. J. A. Sloane_.