login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A119992 a(n) = n-th positive integer which is coprime to n!. 3
1, 3, 7, 11, 17, 19, 29, 31, 37, 41, 47, 53, 61, 67, 71, 73, 83, 89, 101, 103, 107, 109, 127, 131, 137, 139, 149, 151, 163, 167, 179, 181, 191, 193, 197, 199, 223, 227, 229, 233, 241, 251, 263, 269, 271, 277, 283, 293, 307, 311, 313, 317, 337, 347, 349, 353, 359 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Primes not in a(n): {2, 5, 13, 23, 43, 59, 79, 97, 113, 157, 173, 211, 239, 257, 281, 331, 373, 389, 433, 461, 479, 523, 569, 607, 659, ...} - Michael De Vlieger, Oct 02 2017

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..1000

EXAMPLE

1,5,7,11,13,17,19,23,25,...is the sequence of positive integers which are coprime to 4! = 24. 11 is the 4th such integer, so a(4) = 11.

MAPLE

A119992 := proc(n)

    local i, j ;

    j := 0 ;

    i := 1 ;

    while true do

        if gcd(i, n!) = 1 then

            j := j+1 ;

            if j = n then

                return i ;

            break ;

            fi ;

        fi ;

        i := i+1 ;

    od ;

end:

seq(A119992(n), n=1..100) ; # R. J. Mathar, Dec 22 2013

MATHEMATICA

With[{nn = 57}, Table[Select[{1}~Join~Prime@ Range[2 nn], CoprimeQ[n!, #] &][[n]], {n, nn}]] (* Michael De Vlieger, Oct 02 2017 *)

CROSSREFS

Cf. A000142.

Sequence in context: A156284 A045419 A049098 * A023249 A249682 A090513

Adjacent sequences:  A119989 A119990 A119991 * A119993 A119994 A119995

KEYWORD

nonn

AUTHOR

Leroy Quet, Aug 03 2006

EXTENSIONS

More terms from R. J. Mathar, Aug 06 2006

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 23 10:45 EST 2020. Contains 331171 sequences. (Running on oeis4.)