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%I #4 Jul 17 2021 11:22:13
%S 1,2,4,6,13,29,36,55,112,223,264,514,956,1749,2345,2847,5005,8567,
%T 9507,16073,26792,43730,70482,88969,140871,221370,342958,368588,
%U 565510,859401,1290994,1927925,2128165,3142980,4616207,6754033,9810997,14133201,20230329,28744301
%N a(n) is the position of A051451(n) in A025487.
%C Equivalently, the positions of the distinct terms of A003418 in A025487.
%F A025487(a(n)) = A003418(n).
%e A138534(1) = A025487(1) = 1, so a(1) = 1.
%e A138534(2) = A025487(2) = 2, so a(2) = 2.
%e A138534(3) = A025487(4) = 6, so a(3) = 4.
%t lps = Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {_, _}][[;; , 2]]; s = {}; lcms = Union @ Table[LCM @@ Range[n], {n, 1, 31}]; Do[p = Position[lps, lcms[[n]]]; If[p == {}, Break[]]; AppendTo[s, p[[1, 1]]], {n, 1, Length[lcms]}]; s
%Y Cf. A003418, A051451, A025487.
%Y Similar sequences: A098718, A098719, A293635, A306802, A346043.
%K nonn
%O 1,2
%A _Amiram Eldar_, Jul 15 2021