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A098719 Position of n# in A025487. 10
1, 2, 4, 9, 22, 54, 114, 246, 488, 948, 1809, 3327, 6020, 10624, 18246, 30726, 51148, 84074, 135598, 216398, 340886, 529051, 814237, 1240172, 1874464, 2817289, 4195918, 6186286, 9049492, 13121704, 18895821, 27199504, 38892092, 55318849, 78130780, 110028527 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..36.

MATHEMATICA

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 *)

CROSSREFS

Cf. A002110, A025487.

Sequence in context: A317735 A238826 A048211 * A274289 A265023 A343291

Adjacent sequences:  A098716 A098717 A098718 * A098720 A098721 A098722

KEYWORD

nonn

AUTHOR

Jeff Burch, Sep 29 2004

EXTENSIONS

Extended by T. D. Noe, Nov 12 2010

More terms from Michael De Vlieger, Jul 23 2018

STATUS

approved

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Last modified July 27 15:49 EDT 2021. Contains 346308 sequences. (Running on oeis4.)