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 A053243 #7 Oct 27 2023 22:00:45 %S A053243 154,200,259,340,375,466,554,569,673,688,779,869,884,912,989,1095, %T A053243 1232,1276,1394,1409,1493,1513,1630,1645,1719,1805,1819,1923,2027, %U A053243 2042,2117,2153,2162,2208,2240,2345,2480,2542,2662,2706,2850,2871,2886,3003,3078 %N A053243 Numbers n such that A053238(n) = 3. %p A053243 with(numtheory): f := [seq( `if`((sigma(i) > sigma(i+1)),i,print( )), i=1..5000)]; %p A053243 seq( `if`(f[i+1] - f[i] = 3,i,print( )), i=1..1000); %Y A053243 Cf. A000203, A053226, A053238, A053239, A053240, A053241, A053242, A053244, A053245. %K A053243 nonn %O A053243 1,1 %A A053243 _Asher Auel_, Jan 10 2000