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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A247941 Primes p such that all of p - m^2, m = 2, 4, 6, 8, 10, are (positive) primes. 0
167, 227, 677, 1217, 5843, 13163, 15683, 15923, 24107, 122267, 148403, 148727, 157307, 186023, 198413, 227597, 229253, 313997, 338267, 344273, 360293, 372833, 451937, 464483, 469367, 517613, 525257, 541547, 603917, 732233, 742073, 991073, 1006253, 1196873, 1219847, 1328927 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are congruent to (17,23) mod 30.

LINKS

Table of n, a(n) for n=1..36.

MAPLE

isA247941 := proc(p)

    local m ;

    for m from 0 to 10 by 2 do

        if not isprime(p-m^2) then

            return false;

        end if;

    end do:

    return true;

end proc:

for n from 1 to 100000 do

    p := ithprime(n) ;

    if isA247941(p) then

        printf("%d, ", p);

    end if;

end do: # R. J. Mathar, Sep 28 2014

MATHEMATICA

Select[Prime[Range[25, 103000]], AllTrue[#-(2Range[5])^2, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Sep 16 2019 *)

CROSSREFS

Cf. A046132, A246873, A246874 (supersequence).

Sequence in context: A299379 A097400 A142664 * A142329 A088291 A140003

Adjacent sequences:  A247938 A247939 A247940 * A247942 A247943 A247944

KEYWORD

nonn

AUTHOR

Zak Seidov, Sep 27 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 14 22:42 EST 2019. Contains 329987 sequences. (Running on oeis4.)