%I N1999 #17 Apr 04 2020 10:30:44
%S 1,9,475,36799,2082753,262747265,1382741929621,5362709743125,
%T 15980174332775873,24919383499187492303,5370601980438646999929,
%U 4365522871220234892455639,23440607720186374192676171875,277027686598268613994459361577
%N Numerators of higher order Bernoulli numbers.
%C See Nørlund for precise definition.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%H N. E. Nørlund, <a href="http://www-gdz.sub.uni-goettingen.de/cgi-bin/digbib.cgi?PPN373206070">Vorlesungen über Differenzenrechnung</a>, Springer, 1924, p. 461 and p. 147.
%p A213447 := proc(n)
%p local nu ;
%p nu := 2*n+1 ;
%p mul(t-i,i=1..nu) ;
%p int(%,t=0..1) ;
%p abs(numer( %)) ;
%p end proc:
%p seq(A213447(n),n=0..15) ; # _R. J. Mathar_, Jun 26 2012
%t a[n_] := Integrate[Product[t-i, {i, 1, 2n+1}], {t, 0, 1}] // Numerator // Abs;
%t a /@ Range[0, 13] (* _Jean-François Alcover_, Apr 04 2020 *)
%K nonn,frac
%O 0,2
%A _N. J. A. Sloane_, Jun 12 2012