A129753 Floor(prime(n)/nonprime(n)).

2, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3

Offset

1,1

Links

Table of n, a(n) for n=1..50.

Formula

a(n) = floor(A000040(n)/A018252(n)).

a(n) ~ log(n).

Example

a(1) = [2/1] = 2.
a(2) = [3/4] = [0.75] = 0.
a(5) = [11/9] = [1.22222222] = 1.
a(16) = [53/25] = [2.12] = 2.
a(37) = [157/52] = [3.01923077] = 3.

Mathematica

nn=100; Module[{prs=Prime[Range[nn]], non}, non=Take[Complement[ Range[ Last[ prs]], prs], nn]; Floor[#[[1]]/#[[2]]]&/@Thread[{prs, non}]] (* Harvey P. Dale, Aug 29 2012 *)

Crossrefs

Sequence in context: A269247 A330268 A089310 * A356324 A307247 A147693

Adjacent sequences: A129750 A129751 A129752 * A129754 A129755 A129756

Keyword

easy,nonn

Author

Jonathan Vos Post, Jun 02 2007

Status

approved