cp's OEIS Frontend

A351697 32*a(n) is the denominator of the squared circumradius of a cyclic quadrilateral with sides n, n+1, n+2, n+3.

%I A351697 #6 Feb 26 2022 10:49:54
%S A351697 3,15,5,105,210,42,630,990,165,2145,3003,455,5460,7140,1020,11628,
%T A351697 14535,1995,21945,26565,3542,37950,44850,5850,61425,71253,9135,94395,
%U A351697 107880,13640,139128,157080,19635,198135,221445,27417,274170,303810,37310,370230,407253,49665
%N A351697 32*a(n) is the denominator of the squared circumradius of a cyclic quadrilateral with sides n, n+1, n+2, n+3.
%F A351697 a(n) = denominator(b(n)), where b(n) = (8*(2*n^6 + 18*n^5 + 65*n^4 + 120*n^3 + 117*n^2 + 54*n + 9))/(n^4 + 6*n^3 + 11*n^2 + 6*n).
%e A351697 (1/32)*{385/3, 3289/15, 1729/5, 53041/105, 146329/210, 38665/42, ...}
%Y A351697 A351696 gives the corresponding numerators.
%Y A351697 Cf. A000332, A052762, A345665, A351698.
%K A351697 nonn,frac
%O A351697 1,1
%A A351697 _Hugo Pfoertner_, Feb 26 2022