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.

A050944 Numbers k such that sigma(k) > sigma(k+1) > sigma(k+2) > sigma(k+3).

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%I A050944 #19 Aug 01 2023 09:56:32
%S A050944 44,104,116,164,224,272,296,344,356,464,512,560,584,620,704,776,824,
%T A050944 836,860,884,1004,1112,1184,1196,1280,1304,1424,1484,1520,1544,1592,
%U A050944 1616,1700,1724,1880,1904,1952,1964,2024,2036,2120,2144,2276,2324,2372,2384,2444
%N A050944 Numbers k such that sigma(k) > sigma(k+1) > sigma(k+2) > sigma(k+3).
%D A050944 David Wells, The Penguin Dictionary of Curious and Interesting Numbers, entry 44.
%H A050944 Seiichi Manyama, <a href="/A050944/b050944.txt">Table of n, a(n) for n = 1..10000</a>
%e A050944 sigma(44)=84 > sigma(45)=78 > sigma(46)=72 > sigma(47)=48.
%t A050944 Position[Partition[DivisorSigma[1,Range[2500]],4,1],_?(Max[ Differences[ #]]<0&),1,Heads->False]//Flatten (* _Harvey P. Dale_, Sep 13 2020 *)
%Y A050944 Cf. A000203, A050945, A053226.
%K A050944 nonn
%O A050944 1,1
%A A050944 _Jud McCranie_, Jan 02 2000
%E A050944 Name simplified by _Sean A. Irvine_, Aug 20 2021