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!)
A065397 Primes which have no representation p + k*(k+1) / 2, with p prime and k > 0: A000040-Complement of A065396. 5
2, 7, 61, 211 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Finite? (Checked up to A000040(100000) = 1299709.)
Next term > 7000000. - R. J. Mathar, Apr 23 2006
No other terms less than 2*10^9. - T. D. Noe, Mar 26 2008
LINKS
MAPLE
for n from 1 to 7000000 do if isprime(n) = true then foundp := false ; for k from 1 to n do if isprime(n-k*(k+1)/2) = true then foundp := true ; break ; elif n-k*(k+1)/2 < 2 then break ; fi ; od ; if foundp = false then print(n) ; fi ; fi ; od : # R. J. Mathar, Apr 23 2006
CROSSREFS
Sequence in context: A091687 A000892 A211875 * A255904 A046846 A111010
KEYWORD
more,nonn
AUTHOR
Reinhard Zumkeller, Nov 05 2001
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 June 23 18:37 EDT 2024. Contains 373653 sequences. (Running on oeis4.)