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A050945 Six consecutive integers with decreasing values of sigma start at these numbers: sigma(x) > sigma(x+1) > sigma(x+2) > sigma(x+3) > sigma(x+4) > sigma(x+5). 1

%I

%S 20021154,28503474,53728674,224539314,242917674,304178874,341295954,

%T 370845474,377692314,443998554,533007474,610484874,709445274,

%U 855529674,964885074,978052074,1069943874,1114988874,1167961794

%N Six consecutive integers with decreasing values of sigma start at these numbers: sigma(x) > sigma(x+1) > sigma(x+2) > sigma(x+3) > sigma(x+4) > sigma(x+5).

%C There are many examples of 4 consecutive numbers having decreasing values of sigma (see cross references) and there are 83 cases of 6 consecutive numbers with decreasing values of sigma < 4,293,000,000. Interestingly (and for unknown reasons) there are no examples of exactly 5 such consecutive numbers in that range! All known members of the sequence are multiples of 6 and one less than a multiple of 35.

%D David Wells, The Penguin Dictionary of Curious and Interesting Numbers, entry 44.

%e sigma(20021154)=40894848 > sigma(20021155)=35458560 > ... > sigma(20021159)=20021160

%Y Cf. A000203, A050944.

%K nonn

%O 1,1

%A _Jud McCranie_, Jan 02 2000

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Last modified December 2 23:09 EST 2020. Contains 338898 sequences. (Running on oeis4.)