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.

A185275 Products of the first terms of the arithmetic sequence f(n) defined by f(2^k l) = l^{1 - k} (for k a nonnegative integer and l a positive odd integer).

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%I A185275 #22 Oct 19 2018 03:29:03
%S A185275 1,1,3,3,15,15,105,105,945,945,10395,3465,45045,45045,675675,675675,
%T A185275 11486475,11486475,218243025,43648605,916620705,916620705,21082276215,
%U A185275 2342475135,58561878375,58561878375,1581170716125,225881530875,6550564395375,6550564395375
%N A185275 Products of the first terms of the arithmetic sequence f(n) defined by f(2^k l) = l^{1 - k} (for k a nonnegative integer and l a positive odd integer).
%C A185275 Note that f(n) is not always an integer (for example f(12) = 1/3) but Farhi showed in his paper that the product Product_{i = 1..n} f(i) is always an integer.
%H A185275 B. Farhi, <a href="https://arxiv.org/abs/1004.2269">A study of a curious arithmetic function</a>, arXiv:1004.2269 [math.NT], April 13 2010.
%H A185275 Bakir Farhi, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL15/Farhi/farhi3.html">A Study of a Curious Arithmetic Function</a>, Journal of Integer Sequences, Vol. 15 (2012), #12.3.1.
%F A185275 G.f.: G(0)/x -1/x, where G(k)= 1 + x*(2*k+1)/(1 - x/(x + 1/G(k+1))); (continued fraction). - _Sergei N. Gladkovskii_, Jun 07 2013
%Y A185275 Cf. A185021, A055634.
%K A185275 nonn
%O A185275 0,3
%A A185275 _Bakir FARHI_, Jan 21 2012