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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.

A354547 Least number k <= n such that sopfr(k) = sopfr(n).

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%I A354547 #41 Aug 28 2022 21:12:51
%S A354547 1,2,3,4,5,5,7,8,8,7,11,7,13,14,15,15,17,15,19,14,21,13,23,14,21,26,
%T A354547 14,11,29,21,31,21,33,19,35,21,37,38,39,11,41,35,43,26,11,46,47,11,33,
%U A354547 35,51,17,53,11,39,13,57,31,59,35,61,62,13,35,65,39,67,38
%N A354547 Least number k <= n such that sopfr(k) = sopfr(n).
%H A354547 Michael De Vlieger, <a href="/A354547/b354547.txt">Table of n, a(n) for n = 1..10000</a>
%e A354547 For n = 16 = 2^4, sopfr(16) = 2*4 = 8 and 15 = 3 * 5, sopfr(15)= 3 + 5 = 8 and for k < 15, sopfr(k) != 8, hence a(16) = 15.
%t A354547 f[n_] := Plus @@ Times @@@ FactorInteger[n]; f[1] = 0; m = 100; With[{s = Array[f, m]}, Table[FirstPosition[s, s[[n]]][[1]], {n, 1, m}]] (* _Amiram Eldar_, Aug 15 2022 *)
%o A354547 (PARI) sopfr(n) = (n=factor(n))[, 1]~*n[, 2]; \\ A001414
%o A354547 a(n) = my(s=sopfr(n), k=1); while (sopfr(k) != s, k++); k; \\ _Michel Marcus_, Aug 16 2022
%Y A354547 Cf. A001414 (sopfr), A056240, A064364.
%K A354547 nonn
%O A354547 1,2
%A A354547 _Jean-Marc Rebert_, Aug 15 2022