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 A249045 #12 Dec 25 2021 18:35:23 %S A249045 3,9,42,75,108,132,165,198,222,255,288,312,345,378,411,435,468,501, %T A249045 525,558,591,615,648,681,714,738,771,804,828,861,894,918,951,984,1032, %U A249045 1065,1098,1122,1155,1188,1212,1245,1278,1311,1335,1368,1401,1425,1458,1491 %N A249045 Self-numbers (A003052) that are multiples of 3. %D A249045 D. R. Kaprekar, The Mathematics of the New Self Numbers, Privately printed, 311 Devlali Camp, Devlali, India, 1963. %H A249045 Reinhard Zumkeller, <a href="/A249045/b249045.txt">Table of n, a(n) for n = 1..10000</a> %H A249045 D. R. Kaprekar, <a href="/A003052/a003052_2.pdf">The Mathematics of the New Self Numbers</a> [annotated and scanned] %o A249045 (Haskell) %o A249045 a249045 n = a249045_list !! (n-1) %o A249045 a249045_list = filter ((== 0) . flip mod 3) a003052_list %o A249045 -- _Reinhard Zumkeller_, Oct 31 2014 %Y A249045 Cf. A003052, A249046-A249048. %K A249045 nonn,base %O A249045 1,1 %A A249045 _N. J. A. Sloane_, Oct 30 2014