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 A249046 #12 Dec 25 2021 18:35:23 %S A249046 3,42,75,132,165,222,255,312,345,411,435,501,525,591,615,681,714,771, %T A249046 804,861,894,951,984,1032,1065,1122,1155,1212,1245,1311,1335,1401, %U A249046 1425,1491,1515,1581,1614,1671,1704,1761,1794,1851,1884,1941,1974,2022,2055,2112,2145 %N A249046 Self-numbers (A003052) that are multiples of 3 but not of 9. %D A249046 D. R. Kaprekar, The Mathematics of the New Self Numbers, Privately printed, 311 Devlali Camp, Devlali, India, 1963. %H A249046 Reinhard Zumkeller, <a href="/A249046/b249046.txt">Table of n, a(n) for n = 1..1000</a> %H A249046 D. R. Kaprekar, <a href="/A003052/a003052_2.pdf">The Mathematics of the New Self Numbers</a> [annotated and scanned] %o A249046 (Haskell) %o A249046 a249046 n = a249046_list !! (n-1) %o A249046 a249046_list = filter ((> 0) . flip mod 9) a249045_list %o A249046 -- _Reinhard Zumkeller_, Oct 31 2014 %Y A249046 Cf. A003052, A249045-A249048. %K A249046 nonn,base %O A249046 1,1 %A A249046 _N. J. A. Sloane_, Oct 30 2014