A168255 n appears n-th nonprime number times.

1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10

Offset

1,2

Comments

n appears A018252(n) times.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

Module[{nn=20, npn}, npn=Select[Range[nn], !PrimeQ[#]&]; Table[#[[2]], #[[1]]]&/@ Thread[{npn, Range[Length[npn]]}]]//Flatten (* Harvey P. Dale, Dec 19 2021 *)

Crossrefs

Sequence in context: A090532 A003058 A000194 * A097429 A100617 A076471

Adjacent sequences: A168252 A168253 A168254 * A168256 A168257 A168258

Keyword

nonn,easy,less

Author

Jaroslav Krizek, Nov 21 2009

Status

approved