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 A340305 #7 Jan 06 2021 01:56:08
%S A340305 12,45,60,63,84,132,156,175,204,228,275,276,315,325,348,350,372,420,
%T A340305 425,444,475,492,495,516,525,539,540,564,575,585,636,637,660,675,693,
%U A340305 700,708,732,765,780,804,819,833,852,855,876,924,931,948,996,1020,1035,1068
%N A340305 Numbers k such that k and the least number that is larger than k and has the same set of distinct prime divisors as k also has the same prime signature as k.
%C A340305 Numbers k such that k and A065642(k) have the same prime signature (A118914).
%H A340305 Amiram Eldar, <a href="/A340305/b340305.txt">Table of n, a(n) for n = 1..10000</a>
%H A340305 <a href="/index/Pri#prime_signature">Index entries for sequences related to prime signature</a>
%e A340305 12 is a term since the least number that is larger than 12 and has the same set of distinct prime divisors as 12, {2, 3}, is 18 = 2 * 3^2 which also has the same prime signature as 12.
%t A340305 rad[n_] := Times @@ FactorInteger[n][[;; , 1]]; next[n_] := Module[{r = rad[n]}, SelectFirst[Range[n + 1, n^2], rad[#] == r &]]; sig[n_] := Sort @ FactorInteger[n][[;; , 2]]; Select[Range[2, 300], sig[#] == sig[next[#]] &]
%Y A340305 Cf. A065642, A118914.
%Y A340305 Subsequence: A251720.
%K A340305 nonn
%O A340305 1,1
%A A340305 _Amiram Eldar_, Jan 03 2021