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%I #16 Jun 05 2022 08:30:39
%S 1,2,4,9,22,54,114,246,488,948,1809,3327,6020,10624,18246,30726,51148,
%T 84074,135598,216398,340886,529051,814237,1240172,1874464,2817289,
%U 4195918,6186286,9049492,13121704,18895821,27199504,38892092,55318849,78130780,110028527
%N Position of prime(n)# in A025487.
%t Block[{nn = 24, f, s}, f[n_] := {{1}}~Join~Block[{lim = Product[Prime@ i, {i, n}], ww = NestList[Append[#, 1] &, {1}, n - 1], g}, g[x_] := Apply[Times, MapIndexed[Prime[First@ #2]^#1 &, x]]; Map[Block[{w = #, k = 1}, Sort@ Prepend[If[Length@ # == 0, #, #[[1]]], Product[Prime@ i, {i, Length@ w}]] &@ Reap[Do[If[# < lim, Sow[#]; k = 1, If[k >= Length@ w, Break[], k++]] &@ g@ Set[w, If[k == 1, MapAt[# + 1 &, w, k], PadLeft[#, Length@ w, First@ #] &@ Drop[MapAt[# + Boole[i > 1] &, w, k], k - 1]]], {i, Infinity}]][[-1]]] &, ww]]; s = Sort[Join @@ f@ nn]; {1}~Join~Array[Position[s, Product[Prime@ i, {i, #}]] &, nn][[All, 1, 1]]] (* _Michael De Vlieger_, Jul 23 2018 *)
%Y Cf. A002110, A025487.
%K nonn
%O 1,2
%A _Jeff Burch_, Sep 29 2004
%E Extended by _T. D. Noe_, Nov 12 2010
%E More terms from _Michael De Vlieger_, Jul 23 2018
%E Name corrected by _Amiram Eldar_, Jun 05 2022
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