login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A072599 Numbers n such that (n!)^2 - prime(n) is prime. 1
3, 4, 5, 6, 7, 16, 109, 116, 232, 877, 934 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Values associated with 16, 109, 116 and 232 certified prime with Primo. These primes have lengths 27, 353, 382 and 900 digits, respectively.

a(10)-a(11) associated with probable primes. - Robert Price, Aug 23 2014

a(12) > 15300. - Robert Price, Aug 23 2014

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

(5!)^2 - prime(5) = 120^2 - 11 = 14400 - 11 = 14389 is prime, so 5 is a term.

PROG

(PARI) for(n=1, 800, if(isprime((n!)^2-prime(n)), print1(n, ", ")))

CROSSREFS

Cf. A064769 (n such that (n!)^2 + p(n) is prime).

Sequence in context: A078305 A235324 A330373 * A095138 A026475 A101747

Adjacent sequences:  A072596 A072597 A072598 * A072600 A072601 A072602

KEYWORD

nonn,more,hard

AUTHOR

Rick L. Shepherd, Jun 25 2002

EXTENSIONS

a(10)-a(11) from Robert Price, Aug 23 2014

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 10 00:32 EDT 2022. Contains 356026 sequences. (Running on oeis4.)