%I #24 Jul 02 2019 14:13:36
%S 1,3,15,21,45,33,1365,45,765,1995,3465,1035,20475,189,435,7161,58905,
%T 315,959595,4095,142065,148995,108675,14805,2436525,65637,78705,21945,
%U 24795,2655,85180095,135135,546975,8252055
%N From higher-order Bernoulli numbers: denominator of D Number D2n(2n).
%H Gheorghe Coserea, <a href="/A261274/b261274.txt">Table of n, a(n) for n = 0..200</a>
%H Guodong Liu, <a href="http://dx.doi.org/10.1155/2009/605313">A Recurrence Formula for D Numbers D2n(2n-1)</a>, Discrete Dynamics in Nature and Society, Volume 2009 (2009).
%H N. E. Nørlund, <a href="http://gdz.sub.uni-goettingen.de/dms/load/img/?IDDOC=237538">Vorlesungen über Differenzenrechnung</a> Springer 1924, p. 462.
%H <a href="/index/Be#Bernoulli">Index entries for sequences related to Bernoulli numbers.</a>
%t NorlundD[nu_, n_] := (-2)^nu NorlundB[nu, n, n/2];
%t Table[NorlundD[2n, 2 n] // Denominator, {n, 0, 33}] (* _Jean-François Alcover_, Jul 02 2019 *)
%o (PARI) x='x+O('x^66); apply(denominator, select(i->i, Vec(serlaplace((x / log(x + sqrt(1+x^2))) / sqrt(1+x^2)))))
%Y Cf. A001904.
%K nonn,frac
%O 0,2
%A _Gheorghe Coserea_, Aug 13 2015