%I #14 Apr 02 2015 16:37:53
%S 1,3,11,275,7535,73843,1276429,138766067,989263291643,
%T 7301752355616983,55566999221913933083,434538985460750767066613,
%U 3482368080874980096524258963,28534304884670510863221395297153
%N Numerator of Product_{k=1..n} H(k), where H(k) = Sum_{j=1..k} 1/j, the k-th harmonic number.
%e (1)(1 + 1/2)(1 + 1/2 + 1/3) = 1*(3/2)*(11/6) = 11/4, so a(3) = 11.
%t a[n_] := Numerator[ Product[ HarmonicNumber[k], {k, 1, n}]]; Table[ a[n], {n, 14}] (* _Robert G. Wilson v_, Aug 26 2004 *)
%t Numerator[Rest[FoldList[Times,1,HarmonicNumber[Range[20]]]]] (* _Harvey P. Dale_, Apr 02 2015 *)
%o (PARI) hh(n)=sum(i=1,n,1/i); ff(n)=numerator(prod(i=1,n,hh(i))); for (i=1,30,print1(ff(i),",")) \\ Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Aug 23 2004
%Y Cf. A097424.
%K frac,nonn
%O 1,2
%A _Leroy Quet_, Aug 21 2004
%E More terms from Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com) and _Robert G. Wilson v_, Aug 23 2004
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