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%I #12 Nov 25 2022 12:46:45
%S 182,203,287,350,407,558,611,731,779,803,963,1424,1643,2627,2747,3431,
%T 3806,4187,4223,5063,6767,7946,8927,9047,11904,12707,12878,15794,
%U 18923,20567,27263,31175,32111,34427,43139,43811,45854,50165,52592,57479
%N Composite numbers x such that sigma(x+120) = sigma(x)+120.
%C See also A015914, A054799, A033560.
%H Donovan Johnson, <a href="/A054985/b054985.txt">Table of n, a(n) for n = 1..1000</a>
%e a(6)=558, sigma(558)+120=1248+120=1368=sigma(678)=sigma(558+120).
%t Select[Range[60000],CompositeQ[#]&&DivisorSigma[1,#]+120 == DivisorSigma[ 1,#+120]&] (* _Harvey P. Dale_, Nov 25 2022 *)
%o (PARI) isok(n) = !isprime(n) && (sigma(n+120) == (sigma(n) + 120)); \\ _Michel Marcus_, Dec 31 2013
%Y Cf. A015914-A015917, A054799.
%K nonn
%O 1,1
%A _Labos Elemer_, May 29 2000
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