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A392104

a(n) = prime(A391796(n)).

5, 23, 47, 251, 1889, 7793, 43451, 243161, 726893, 759821, 1820123, 1820111, 10141499, 19725479, 19725473, 136209239, 400414127, 400414121, 489144659, 489144599, 766319201, 766319189, 21549657581, 21549657551, 21549657539, 140432294399, 140432294381, 437339303279

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..28.

MATHEMATICA

t = Table[Mod[Prime[nn], 3], {nn, 10^8}]; (* A039701 *)

u = Map[SequencePosition[t, Flatten[Join[{ConstantArray[2, #], 1}]], 1] &, Range[21]]

Prime[Table[First[Flatten[u[[n]]]], {n, 1, 21}]]

(* Peter J. C. Moses, Dec 11 2025 *)

PROG

(Python)