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 A080258 #34 Feb 23 2024 07:25:59
%S A080258 12,16,18,20,28,44,45,50,52,63,68,75,76,81,92,98,99,116,117,124,147,
%T A080258 148,153,164,171,172,175,188,207,212,236,242,244,245,261,268,275,279,
%U A080258 284,292,316,325,332,333,338,356,363,369,387,388,404,412,423,425,428,436
%N A080258 Either 4th power of a prime, or product of a prime and the square of a different prime.
%C A080258 Union of A030514 and A054753.
%C A080258 Numbers that equal the product of the proper divisors of their proper divisors. - _Scott R. Shannon_, Jul 04 2021
%H A080258 Hugo Pfoertner, <a href="/A080258/b080258.txt">Table of n, a(n) for n = 1..10000</a>
%F A080258 A080256(a(n)) = 5.
%F A080258 A002033(a(n)) = 8. - _Juri-Stepan Gerasimov_, Sep 26 2009
%e A080258 81=3*3*3*3 and 50=2*5*5 are terms.
%t A080258 Module[{nn=20,p4,sdp},p4=Prime[Range[nn]]^4;sdp=#[[1]] #[[2]]^2&/@ Select[ Tuples[Prime[Range[nn]],2],#[[1]]!=#[[2]]&];Take[Join[p4,sdp]// Union,40]] (* _Harvey P. Dale_, Jan 31 2021 *)
%o A080258 (PARI) is(n)=my(f=factor(n)[,2]~); f==[4] || f==[2,1] || f==[1,2] \\ _Charles R Greathouse IV_, Oct 16 2015
%Y A080258 Cf. A007964, A058080, A001221, A001222, A002033, A006881, A030078.
%K A080258 nonn
%O A080258 1,1
%A A080258 _Reinhard Zumkeller_, Feb 10 2003