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 A075787 #7 Mar 08 2025 20:30:18
%S A075787 4,8,64,400,484,2048,4624,6084,6400,8000,8464,26244,28224,40000,40804,
%T A075787 48400,64000,68644,88804,228484,242064,248004,446224,462400,608400,
%U A075787 640000,806404,824464,846400,868624,2022084,2226064,2244004,2624400
%N A075787 Even-digit perfect powers.
%t A075787 Do[ If[ Union[ EvenQ[ IntegerDigits[n]]] == {True} && Apply[GCD, Last[ Transpose[ FactorInteger[n]]]] > 1, Print[n]], {n, 4, 2822399, 2}]
%Y A075787 Cf. A001597, A076442.
%K A075787 easy,base,nonn
%O A075787 1,1
%A A075787 _Zak Seidov_, Oct 10 2002
%E A075787 Edited, corrected and extended by _Robert G. Wilson v_, Oct 11 2002