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 A348018 #8 Sep 25 2021 04:45:10
%S A348018 1,2,4,3,6,9,10,5,7,14,16,12,20,21,24,8,28,15,31,22,35,36,39,19,17,44,
%T A348018 13,32,48,50,51,11,56,59,60,23,65,67,68,33,71,73,75,52,43,81,84,27,30,
%U A348018 37,90,64,94,29,97,46,102,104,107,74,110,111,62,18,117,119
%N A348018 a(n) is the index of A064549(n) = n * Product_{p prime|n} p in the sequence of powerful numbers (A001694).
%C A348018 A permutation of the positive integers.
%C A348018 The inverse permutation of A306458.
%H A348018 Amiram Eldar, <a href="/A348018/b348018.txt">Table of n, a(n) for n = 1..10000</a>
%F A348018 A001694(a(n)) = A064549(n).
%F A348018 A306458(a(n)) = a(A306458(n)) = n.
%F A348018 The fixed points of this permutation are 1, 2, 12, 1208, 1256, 1288 and no more below 3*10^5.
%e A348018 The sequence of powerful numbers (A001694) begins with 1, 4, 8, 9, ...
%e A348018 The position of A064549(1) = 1 in A001694 is 1, so a(1) = 1.
%e A348018 The position of A064549(3) = 9 in A001694 is 4, so a(3) = 4.
%t A348018 powQ[n_] := AllTrue[FactorInteger[n][[;; , 2]], # > 1 &]; pows = Join[{1}, Select[Range[10^4], powQ]]; TakeWhile[Table[FirstPosition[pows, n * Times @@ (First /@ FactorInteger[n])][[1]], {n, 1, 100}], NumericQ]
%Y A348018 Cf. A001694, A064549, A306458.
%K A348018 nonn
%O A348018 1,2
%A A348018 _Amiram Eldar_, Sep 24 2021