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