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A050944
Numbers k such that sigma(k) > sigma(k+1) > sigma(k+2) > sigma(k+3).
6
44, 104, 116, 164, 224, 272, 296, 344, 356, 464, 512, 560, 584, 620, 704, 776, 824, 836, 860, 884, 1004, 1112, 1184, 1196, 1280, 1304, 1424, 1484, 1520, 1544, 1592, 1616, 1700, 1724, 1880, 1904, 1952, 1964, 2024, 2036, 2120, 2144, 2276, 2324, 2372, 2384, 2444
OFFSET
1,1
REFERENCES
David Wells, The Penguin Dictionary of Curious and Interesting Numbers, entry 44.
LINKS
EXAMPLE
sigma(44)=84 > sigma(45)=78 > sigma(46)=72 > sigma(47)=48.
MATHEMATICA
Position[Partition[DivisorSigma[1, Range[2500]], 4, 1], _?(Max[ Differences[ #]]<0&), 1, Heads->False]//Flatten (* Harvey P. Dale, Sep 13 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jud McCranie, Jan 02 2000
EXTENSIONS
Name simplified by Sean A. Irvine, Aug 20 2021
STATUS
approved