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Denominators of the partial sums of the reciprocals of the numbers (k + 1)*(6*k + 5) = A049452(k+1).
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%I #11 Nov 29 2017 03:08:20

%S 5,110,5610,258060,1496748,17462060,715944460,67298779240,

%T 32101517697480,378797908830264,24621864073967160,1748152349251668360,

%U 1748152349251668360,145096644987888473880,2582720280784414835064,490716853349038818662160,49562402188252920684878160

%N Denominators of the partial sums of the reciprocals of the numbers (k + 1)*(6*k + 5) = A049452(k+1).

%C The corresponding numerators are given in A294964. There details are found.

%H Robert Israel, <a href="/A294965/b294965.txt">Table of n, a(n) for n = 0..640</a>

%F a(n) = denominator(V(6,5;n)) with V(6,5;n) = Sum_{k=0..n} 1/((k + 1)*(6*k + 5)) = Sum_{k=0..n} 1/A049452(k+1) = Sum_{k=0..n} (1/(k + 5/6) - 1/(k + 1)).

%e For the rationals V(6,5;n) see A294964.

%p map(denom, ListTools:-PartialSums([seq(1/(k+1)/(6*k+5),k=0..20)])); # _Robert Israel_, Nov 29 2017

%o (PARI) a(n) = denominator(sum(k=0, n, 1/((k + 1)*(6*k + 5)))); \\ _Michel Marcus_, Nov 27 2017

%Y Cf. A049452, A294964.

%K nonn,frac,easy

%O 0,1

%A _Wolfdieter Lang_, Nov 27 2017