The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A247941

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A247941

Primes p such that all of p - m^2, m = 2, 4, 6, 8, 10, are (positive) primes.
(history; published version)

#13 by Harvey P. Dale at Mon Sep 16 17:23:58 EDT 2019

STATUS

editing

approved

#12 by Harvey P. Dale at Mon Sep 16 17:23:54 EDT 2019

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 *)

STATUS

approved

editing

#11 by Jon E. Schoenfield at Thu Aug 06 21:05:09 EDT 2015

STATUS

editing

approved

#10 by Jon E. Schoenfield at Thu Aug 06 21:05:06 EDT 2015

CROSSREFS

Cf. A046132, A246873, A246874 (super-sequencesupersequence).

STATUS

approved

editing

#9 by Bruno Berselli at Sun Sep 28 11:28:42 EDT 2014

STATUS

reviewed

approved

#8 by R. J. Mathar at Sun Sep 28 11:28:11 EDT 2014

STATUS

proposed

reviewed

#7 by R. J. Mathar at Sun Sep 28 11:28:06 EDT 2014

STATUS

editing

proposed

#6 by R. J. Mathar at Sun Sep 28 11:27:58 EDT 2014

NAME

Primes p such that all of p - m^2, m = 2, 4, 6, 8, 10, are all (positive) primes.

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

CROSSREFS

Cf. A046132, A246873, A246874 (super-sequence).

STATUS

proposed

editing

#5 by Zak Seidov at Sun Sep 28 08:03:55 EDT 2014

STATUS

editing

proposed

#4 by Zak Seidov at Sat Sep 27 11:30:43 EDT 2014

COMMENTS

All terms are congruent to 5 (17,23) mod 630.