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 A333427 #9 Mar 21 2020 04:05:45 %S A333427 1,8,24,32,44,64,65,132,212,224,244,245,296,368,424,425,468,560,656, %T A333427 720,728,737,869,1056,1088,1416,1572,1728,2100,2312,2324,2344,2345, %U A333427 2524,2525,2568,2600,2672,2820,2960,3032,3132,3156,3200,3288,3392,3444,4096,4424 %N A333427 Numbers k such that k and k+1 are both primorial base Niven numbers (A333426). %H A333427 Amiram Eldar, <a href="/A333427/b333427.txt">Table of n, a(n) for n = 1..10000</a> %e A333427 1 is a term since 1 and 2 are both primorial base Niven numbers. %t A333427 max = 6; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; primNivenQ[n_] := Divisible[n, Plus @@ IntegerDigits[n, MixedRadix[bases]]]; q1 = primNivenQ[1]; seq = {}; Do[q2 = primNivenQ[n]; If[q1 && q2, AppendTo[seq, n - 1]]; q1 = q2, {n, 2, nmax}]; seq %Y A333427 Cf. A328205, A328209, A328213, A330927, A330931, A333426. %K A333427 nonn %O A333427 1,2 %A A333427 _Amiram Eldar_, Mar 20 2020