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.

A127707 Number of commutative rings with 1 containing n elements.

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%I A127707 #27 Apr 19 2022 07:22:24
%S A127707 1,1,1,4,1,1,1,10,4,1,1,4,1,1,1,37,1,4,1,4,1,1,1,10,4,1,11,4,1,1,1,
%T A127707 109,1,1,1,16,1,1,1,10,1,1,1,4,4,1,1,37,4,4,1,4,1,11,1,10,1,1,1,4,1,1,
%U A127707 4
%N A127707 Number of commutative rings with 1 containing n elements.
%C A127707 Is this a multiplicative function?
%C A127707 Answer: yes! See the Eric M. Rains link for a proof for the result for all unital rings; restricting to commutative rings does not affect the essence of the proof. - _Jianing Song_, Feb 02 2020
%H A127707 C. Noebauer, <a href="https://web.archive.org/web/20080111141811/http://www.algebra.uni-linz.ac.at/~noebsi/">Home page</a> and <a href="https://web.archive.org/web/20061002201537/http://www.algebra.uni-linz.ac.at/~noebsi/ringtable.html">Table of numbers of small rings</a> [Archived copies from web.archive.org]
%H A127707 Eric M. Rains, <a href="/A037291/a037291.txt">The number of unital rings with n elements is a multiplicative function of n.</a>
%F A127707 a(n) = A037291(n) - A127708(n). - _Bernard Schott_, Apr 19 2022
%Y A127707 Cf. A037289, A037291, A127708, A027623, A307000, A341202.
%K A127707 more,nice,nonn,mult
%O A127707 1,4
%A A127707 Hugues Randriam (randriam(AT)enst.fr), Jan 24 2007
%E A127707 Keyword 'mult' added by _Jianing Song_, Feb 02 2020
%E A127707 a(32)-a(63) using Nöbauer's data added by _Andrey Zabolotskiy_, Apr 18 2022
%E A127707 a(32) = 109 corrected by _Bernard Schott_, Apr 19 2022