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 A385516 #5 Jul 02 2025 16:56:26 %S A385516 1,4,8,9,32,64,81,841,961 %N A385516 Perfect powers whose digits are in strictly decreasing order. %t A385516 perfectPowerQ[n_] := n==1 || GCD @@ FactorInteger[n][[All, 2]] > 1; (* A001597 *) Select[Range[1000], perfectPowerQ[#] && Max[Differences[IntegerDigits[#]]]<0 &] %Y A385516 Cf. A001597, A009995, A355060, A355062, A355063, A385517. %K A385516 nonn,base,fini,full %O A385516 1,2 %A A385516 _Stefano Spezia_, Jul 01 2025