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 A228961 #9 Nov 11 2013 17:23:01 %S A228961 114,120,228,234,240,282,348,420,582,588,654,660,708,840,1002,1008, %T A228961 1014,1068,1122,1242,1248,1254,1260,1380,1434,1542,1548,1674,1794, %U A228961 1800,1908,1914,1998,2094,2100,2208,2214,2220,2262,2268,2328,2334,2340,2502,2508 %N A228961 Smallest sets of 4 consecutive abundant numbers in arithmetic progression. The initial abundant number is listed. %H A228961 Shyam Sunder Gupta, <a href="/A228961/b228961.txt">Table of n, a(n) for n = 1..5000</a> %e A228961 114, 120, 126, 132 is the smallest set of 4 consecutive abundant numbers in arithmetic progression so 114 is in the list. %t A228961 AbundantQ[n_] := DivisorSigma[1, n] > 2 n; m = 2; z1 = 18; cd = 6; a = {}; Do[If[AbundantQ[n], If[n - z1 == cd, m = m + 1; If[m > 3, AppendTo[a, n - 3*cd]], m = 2; cd = n - z1]; z1 = n], {n, 19, 1000000}];a %Y A228961 Cf. A005101, A228433, A228844. %K A228961 nonn %O A228961 1,1 %A A228961 _Shyam Sunder Gupta_, Nov 10 2013