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%I #37 Jan 03 2019 17:48:57
%S 12,20,2520,27720,720720,4084080,5173168,80313433200,2329089562800,
%T 13127595717600,485721041551200,2844937529085600,1345655451257488800,
%U 3099044504245996706400,54749786241679275146400,3230237388259077233637600
%N Denominators of harmonic numbers when the numerators are divisible by squares of primes >= 5 in the case of Wolstenholme's Theorem.
%C From _Bernard Schott_, Dec 28 2018: (Start)
%C By Wolstenholme's Theorem, if p prime >= 5, the numerator of the harmonic number H_{p-1} is always divisible by p^2. The obtained quotients are in A061002.
%C The numerators of H_7 and H_{29} are also divisible by prime squares, respectively by 11^2 and 43^2, but not in the case of Wolstenholme's theorem, so the denominators of H_7 and H_{29} are not in this sequence here. (End)
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WolstenholmesTheorem.html">Wolstenholme's Theorem</a>
%e a(1)=12 because the numerator of H_4 = 25/12 is divisible by the square of 5;
%e a(2)=20 because the numerator of H_6 = 49/20 is divisible by the square of 7.
%t a[p_] := Denominator[HarmonicNumber[p - 1]]; a /@ Prime@Range[3, 20] (* _Amiram Eldar_, Dec 28 2018 *)
%Y Cf. A076637, A185399.
%K nonn,frac
%O 1,1
%A Michael Gilleland (megilleland(AT)yahoo.com), Oct 23 2002
%E More terms added by _Amiram Eldar_, Dec 04 2018
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