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 A335398 #9 Jun 07 2020 01:19:53 %S A335398 2068373,2948373,3571749,3916374,4730373,4757750,6755750,8109125, %T A335398 11290872,12248872,13071750,13648311,13903623,15278247,15448374, %U A335398 15449749,16793622,17446374,17991125,19407624,20080248,20250375,21594248,22577750,24190758,25297622,26140373 %N A335398 Starts of runs of 4 consecutive numbers that have an equal number of unitary and nonunitary divisors (A048109). %H A335398 Amiram Eldar, <a href="/A335398/b335398.txt">Table of n, a(n) for n = 1..10000</a> %e A335398 2068373 is a term since 2068373, 2068374, 2068375 and 2068376 each have an equal number of unitary and nonunitary divisors. 2068373 and 2068375 each have 4 unitary divisors and 4 nonunitary divisors, 2068374 has 32 unitary divisors and 32 nonunitary divisors, and 2068376 has 8 unitary divisors and 8 nonunitary divisors. %t A335398 q[n_] := DivisorSigma[0, n] == 2^(PrimeNu[n] + 1); v = q /@ Range[4]; seq = {}; Do[v = Append[Drop[v, 1], q[k]]; If[And @@ v, AppendTo[seq, k - 3]], {k, 5, 10^7}]; seq %Y A335398 Subsequence of A048109, A335328 and A335397. %Y A335398 Cf. A000005, A034444, A048105. %K A335398 nonn %O A335398 1,1 %A A335398 _Zak Seidov_ and _Amiram Eldar_, Jun 06 2020