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.

A360054 Number of odd amicable pairs where the smaller term of the pair is less than 10^n.

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%I A360054 #35 Jan 28 2023 12:23:15
%S A360054 0,0,0,0,3,8,21,55,154,412,1088,2632,6532,15371,35218,79982,180061,
%T A360054 402560,894404,1975742
%N A360054 Number of odd amicable pairs where the smaller term of the pair is less than 10^n.
%C A360054 The list starts with n=1.
%C A360054 Comparing with the numbers of even amicable pairs in A066873, up to 10^4, the proportion of odd amicable pairs is 0%; up to 10^5 it is 23% and up to 10^10 is 28.9%. Up to 10^15, it is 40.4% and up to 10^19 this percentage is 45.9%. It is possible that this trend holds true for more amicable pairs, and thus most amicable number pairs are odd.
%D A360054 Song Y. Yan, Perfect, Amicable and Sociable Numbers. A Computational Approach, World Scientific, 1996, pages 151 - 153.
%H A360054 Sergei Chernykh, <a href="http://sech.me/ap/">Amicable pairs list</a>
%H A360054 Zoltan Galantai, <a href="https://eltehu-my.sharepoint.com/:t:/g/personal/galantai_gtk_elte_hu/EV04AhLUewBAoFvqxSZblR8BuMe_SYQ9a-nJG2L-hkLzRQ?e=TzRGHX">Number of odd amicable pairs where the smaller term of the pair is less than 10^20</a>
%Y A360054 Cf. A066873, A259180, A262623, A262622, A262625, A005408.
%K A360054 nonn,more
%O A360054 1,5
%A A360054 _Zoltan Galantai_, Jan 23 2023