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 A270571 #8 Feb 24 2019 02:13:32 %S A270571 12,24,36,48,60,72,84,96,105,108,120,132,144,156,168,180,192,204,216, %T A270571 228,240,252,264,276,288,300,312,315,324,336,348,360,372,384,396,408, %U A270571 420,432,444,456,468,480,492,504,516,525,528,540,552,564,576,588,600 %N A270571 Numbers with at least one arithmetic progression of four consecutive divisors. %C A270571 Contrast A094529 where the divisors in arithmetic progression do not have to be consecutive. %H A270571 Harvey P. Dale, <a href="/A270571/b270571.txt">Table of n, a(n) for n = 1..1000</a> %e A270571 348 is included because its divisors are 1, 2, 3, 4, 6, 12, 29, 58, 87, 116, 174, and 348, and the first four are in arithmetic progression. %t A270571 ap4dQ[n_]:=Count[Partition[Divisors[n],4,1],_?(Length[ Union[ Differences[ #]]] == 1&)]>0; Select[ Range[700],ap4dQ] %Y A270571 Cf. A091011, A094529, A094530. %K A270571 nonn %O A270571 1,1 %A A270571 _Reinhard Zumkeller_, Mar 19 2016 %E A270571 Edited by _Harvey P. Dale_ and _Alois P. Heinz_, Mar 19 2016