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A338518 Primes p such that (p*s) mod q and (p*s) mod r are prime, where q,r,s are the next primes after p. 2
3, 29, 37, 41, 53, 71, 73, 83, 107, 149, 157, 173, 179, 197, 199, 277, 283, 311, 317, 367, 401, 433, 491, 499, 509, 563, 643, 683, 727, 769, 773, 809, 829, 839, 877, 953, 1013, 1063, 1097, 1109, 1153, 1171, 1181, 1297, 1307, 1361, 1367, 1399, 1439, 1453, 1511, 1543, 1553, 1567, 1747, 1847, 1913 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(4) = 41 is a member because with p=41, q=43, r=47 and s=53 we have (41*53) mod 43 = 23 and (41*53) mod 47 = 11, and 23 and 11 are prime.

MAPLE

p2:= 2: p3:= 3: p4:= 5: R:= NULL: count:= 0:

while count < 100 do

p1:= p2; p2:= p3; p3:= p4;

p4:= nextprime(p4);

r2:= (p1*p4) mod p2;

r3:= (p1*p4) mod p3;

if isprime(r2) and isprime(r3) then

R:= R, p1; count:= count+1;

fi

od:

R;

CROSSREFS

Cf. A338751.

Sequence in context: A189571 A055062 A086174 * A178642 A125854 A167278

Adjacent sequences: A338515 A338516 A338517 * A338519 A338520 A338521

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Nov 06 2020

STATUS

approved

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Last modified March 5 10:10 EST 2023. Contains 360899 sequences. (Running on oeis4.)