cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A225165 Denominators of the sequence s(n) of the sum resp. product of fractions f(n) defined recursively by f(1) = 6/1; f(n+1) is chosen so that the sum and the product of the first n terms of the sequence are equal.

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%I A225165 #5 May 01 2013 12:22:43
%S A225165 1,5,155,176855,265770796655,679134511201261085170655,
%T A225165 4943777738415359153962876938905400001585992709055
%N A225165 Denominators of the sequence s(n) of the sum resp. product of fractions f(n) defined recursively by f(1) = 6/1; f(n+1) is chosen so that the sum and the product of the first n terms of the sequence are equal.
%C A225165 Numerators of the sequence s(n) of the sum resp. product of fractions f(n) is A165424(n+2), hence sum(A165424(i+1)/A225158(i),i=1..n) = product(A165424(i+1)/A225158(i),i=1..n) = A165424(n+2)/a(n) = A173501(n+2)/a(n).
%F A225165 a(n) = 6^(2^(n-1))*b(n) where b(n)=b(n-1)-b(n-1)^2 with b(1)=1/6.
%e A225165 f(n) = 6, 6/5, 36/31, 1296/1141, ...
%e A225165 6 + 6/5 = 6 * 6/5 = 36/5; 6 + 6/5 + 36/31 = 6 * 6/5 * 36/31 = 1296/155; ...
%e A225165 s(n) = 1/b(n) = 6, 36/5, 1296/155, ...
%p A225165 b:=proc(n) option remember; b(n-1)-b(n-1)^2; end:
%p A225165 b(1):=1/6;
%p A225165 a:=n->6^(2^(n-1))*b(n);
%p A225165 seq(a(i),i=1..8);
%Y A225165 Cf. A076628, A165424, A173501, A225158.
%K A225165 nonn
%O A225165 1,2
%A A225165 _Martin Renner_, Apr 30 2013