A080404 a(n)=A007947[A055932(n)]; the sequence consists of primorial numbers;.

2, 2, 6, 2, 6, 2, 6, 6, 30, 2, 6, 6, 6, 30, 2, 6, 30, 6, 6, 30, 2, 6, 30, 6, 30, 6, 210, 6, 30, 2, 30, 6, 30, 6, 30, 6, 210, 6, 30, 30, 6, 2, 30, 6, 30, 210, 6, 30, 30, 6, 30, 210, 6, 30, 30, 6, 2, 210, 30, 6, 30, 210, 6, 30, 30, 6, 210, 30, 6, 30, 210, 6, 30, 210, 30, 6, 2, 210, 30, 30, 6

Offset

1,1

Links

Michael De Vlieger, Table of n, a(n) for n = 1..10000

Mathematica

With[{P = FoldList[Times, Prime@ Range@ Max@ #]}, Map[P[[#]] &, #]] &@ Map[PrimeNu@ # &, Select[Range[10^4], Last[#] == Length[#] &@ PrimePi@ FactorInteger[#][[All, 1]] &]] (* Michael De Vlieger, Feb 06 2020 *)

Crossrefs

Cf. A007947, A002110, A055932.

Sequence in context: A278159 A071796 A121699 * A247451 A167268 A278162

Adjacent sequences: A080401 A080402 A080403 * A080405 A080406 A080407

Keyword

nonn

Author

Labos Elemer, Mar 19 2003

Status

approved