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 A373841 #9 Jun 20 2024 16:57:51 %S A373841 0,5,9,10,13,14,18,23,27,28,33,34,37,38,42,47,51,52,55,56,61,62,66,71, %T A373841 75,76,79,80,84,89,90,95,99,100,103,104,108,113,117,118,123,124,127, %U A373841 128,132,137,141,142,145,146,151,152,156,161,165,166,169,170,174,179,180,185,189,190,193,194,198,203,207,208 %N A373841 Numbers whose digital sum in the primorial base is a multiple of 3. %C A373841 If x and y are terms and if A329041(x,y) = 1 (i.e., when adding x and y together will not generate any carries in the primorial base), then x+y is also a term. %H A373841 Antti Karttunen, <a href="/A373841/b373841.txt">Table of n, a(n) for n = 1..12000</a> %H A373841 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a> %e A373841 A049345(47) = 1221, so A276150(47) = 6, therefore 47 is included in this sequence. %o A373841 (PARI) isA373841 = A373840; %Y A373841 Cf. A049345, A276150, A329041, A373839 (subsequence), A373840 (characteristic function). %Y A373841 Cf. also A373831. %K A373841 nonn,base %O A373841 1,2 %A A373841 _Antti Karttunen_, Jun 20 2024