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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.

A330704 a(n) is the least number k for which A330437(k) = n.

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%I A330704 #27 Feb 22 2020 10:41:13
%S A330704 1,4,12,27,26,182,183,319,280,842,1045,1718,1989,1985,1983,1922,5673,
%T A330704 8546,11760,13371,15606,16659,15827,15732,15833,15210,15416,15707,
%U A330704 15334,15251,15006,14812,14674,14787,14786,55911,137068,283221,283091,301659,301655,292032,294932,256000
%N A330704 a(n) is the least number k for which A330437(k) = n.
%C A330704 The graph of the sequence looks like a staircase: the consecutive terms differ very little, then rise significantly, then again differ very little and so on. Could someone explain this behavior?
%e A330704 As n = 26 is the least number with the trajectory of length 5, (26, 27, 35, 39, 41), a(5) = 26.
%t A330704 Clear[f,it,order,seq]; f[n_]:=f[n]=n-1+n/FactorInteger[n][[-1]][[1]]; it[k_,n_]:=it[k,n]=f[it[k,n-1]]; it[k_,1]=k; order[n_]:=order[n]=SelectFirst[Range[1,100], it[n,#]==it[n,#+1]&]; seq[n_]:=seq[n]=SelectFirst[Range[350000],order[#]==n&]; seq/@Range[61]
%Y A330704 Cf. A330437.
%K A330704 nonn,look
%O A330704 1,2
%A A330704 _Elijah Beregovsky_, Feb 16 2020