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A286178 Denominator of Sum_{i=1..n}(A285388(i)*A285389(i+1))/(A285388(i+1)*A285389(i)). 1

%I #13 Dec 12 2023 13:43:50

%S 35,255255,100280245065,2152114239059719935,

%T 1952792905443446363385953865,40347439369046572433179287578305731225,

%U 772786810821609466400679930812513688804332910188025,73222791895598040395939625423986137213129917738912050041051075

%N Denominator of Sum_{i=1..n}(A285388(i)*A285389(i+1))/(A285388(i+1)*A285389(i)).

%C Conjecture: the factorization of a(n) contains all primes 5 < p < 2*(n+1)^2.

%t a388[i_] := Numerator[2^(1 - 2 i^2) i Binomial[2 i^2, i^2]]; a389[i_] := Denominator[2^(1 - 2 i^2) i Binomial[2 i^2, i^2]]; Denominator[Table[Sum[(a388[i]/a389[i])/((a388[i + 1]/a389[i + 1])), {i, 1, n}], {n, 1, 10}]]

%Y Cf. A285388, A285389, A286179 (numerators).

%K nonn,frac

%O 1,1

%A _Ralf Steiner_, May 04 2017

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Last modified September 13 04:25 EDT 2024. Contains 375859 sequences. (Running on oeis4.)