login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A085971 Union of primes and numbers that are not prime powers (A000040, A024619). 5
2, 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 26, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A025475;

A085972(n) = Max{k: a(k)<=n};

different from A007916 and A052485, as a(28)=36;

A085818(a(n)) = A000040(n).

LINKS

Table of n, a(n) for n=1..68.

FORMULA

a(n) = n + o(sqrt n). - Charles R Greathouse IV, Oct 19 2015

PROG

(PARI) is(n)=isprimepower(n)<2 && n>1 \\ Charles R Greathouse IV, Oct 19 2015

CROSSREFS

Sequence in context: A089105 A028769 A094784 * A175082 A007916 A052485

Adjacent sequences:  A085968 A085969 A085970 * A085972 A085973 A085974

KEYWORD

nonn,easy

AUTHOR

Reinhard Zumkeller, Jul 06 2003

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified January 23 01:55 EST 2018. Contains 298093 sequences.