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A306931 Primes p of the form 8*k + 3 such that every prime divisor of p-2 has the form 8*t + 7. 1
163, 331, 499, 1171, 1459, 2179, 2203, 2371, 2683, 3019, 5179, 5923, 6043, 6211, 6379, 6883, 7219, 7411, 7723, 8059, 8443, 8563, 9643, 10099, 10651, 10723, 11083, 11131, 11251, 12739, 12763, 13099, 13963, 14779, 14851, 15091, 15451, 16963, 17203 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

L. E. Dickson, History of the Theory of Numbers. Carnegie Institute Public. 256, Washington, DC, Vol. 1, 1919; Vol. 2, 1920; Vol. 3, 1923, see vol. 2, p. 476.

LINKS

Table of n, a(n) for n=1..39.

MAPLE

with(numtheory);

s:=[];

for n from 3 to 5000 do

p:=ithprime(n); p2:=((p+16) mod 8);

if (p2=3) then sw:=1;

   for q in factorset(p-2) do if (q mod 8) <> 7 then sw:=-1; break; fi; od:

   if sw=1 then s:=[op(s), p]; fi;

fi;

od:

s; # A306931

CROSSREFS

Sequence in context: A142772 A212398 A157952 * A142427 A142237 A142283

Adjacent sequences:  A306928 A306929 A306930 * A306932 A306933 A306934

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Mar 16 2019

STATUS

approved

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Last modified July 15 14:33 EDT 2019. Contains 325031 sequences. (Running on oeis4.)