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Denominators of first difference of squares of harmonic numbers A001008/A002805.
2

%I #8 Aug 09 2023 07:06:26

%S 1,4,9,48,150,90,490,2240,11340,2520,152460,83160,2342340,2522520,

%T 540540,11531520,104144040,110270160,737176440,775975200,162954792,

%U 56904848,1368302936,2141691552,111546435000,116008292400,1084231348200

%N Denominators of first difference of squares of harmonic numbers A001008/A002805.

%C The corresponding numerators are given in A103932. For the rationals see the link there.

%F a(n)=numerator(r(n)), with the rationals r(n)=H(n)^2-H(n-1)^2 where H(n)= A001008(n)/A002805(n), n>=1, H(0):=0.

%t Denominator[Differences[HarmonicNumber[Range[0,30]]^2]] (* _Harvey P. Dale_, Sep 09 2012 *)

%K nonn,easy,frac

%O 1,2

%A _Wolfdieter Lang_, Mar 24 2005

%E Offset corrected by _Mohammed Yaseen_, Aug 09 2023