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 A332456 #8 Feb 15 2020 21:09:25 %S A332456 9,67,163,193,201,202,271,338,469,489,505,547,579,606,670,673,729,813, %T A332456 982,1087,1111,1123,1139,1141,1153,1201,1223,1351,1354,1407,1414,1423, %U A332456 1474,1515,1543,1601,1630,1641,1642,1791,1873,1897,1930,1966,2010,2017,2019,2077,2083,2088,2323,2326,2371,2447,2455,2467,2503 %N A332456 Numbers k such that sigma(sigma(k)) is congruent to 6 modulo 8. %H A332456 Antti Karttunen, <a href="/A332456/b332456.txt">Table of n, a(n) for n = 1..10000</a> %H A332456 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %o A332456 (PARI) isA332456(n) = (6==(sigma(sigma(n))%8)); %Y A332456 Cf. A000203, A051027, A332226, A332457, A332458. %K A332456 nonn %O A332456 1,1 %A A332456 _Antti Karttunen_, Feb 15 2020