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%I #18 Sep 08 2022 08:46:09
%S 3577,14773,2843579
%N Numbers n such that sigma(n+5) - sigma(n) = n + 5.
%C Also numbers n such that A001065(n+5) = A000203(n). - _Michel Marcus_, Sep 06 2014
%C a(4) (if it exists) > 10^11. - _Hiroaki Yamanouchi_, Sep 10 2014
%C a(4) (if it exists) > 10^13. - _Giovanni Resta_, Jul 13 2015
%e Number 3577 is in sequence because sigma(3577+5) - sigma(3577) = 7800 - 4218 = 3582 = 3577 + 5.
%o (Magma) [n:n in[1..10^7] | SumOfDivisors(n+5)-SumOfDivisors(n) eq n+5]
%o (PARI)
%o for(n=1,10^7,if(sigma(n+5)-sigma(n)==n+5,print1(n,", "))) \\ _Derek Orr_, Sep 05 2014
%Y Cf. A000203, A067816, A246851, A246852, A246853, A246854.
%K nonn,bref,more
%O 1,1
%A _Jaroslav Krizek_, Sep 05 2014
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