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A338836 Primes p such that 2*p^2-q^2 and 2*q^2-p^2 are prime, where q is the next prime after p. 1
53, 103, 397, 479, 1049, 1499, 1901, 1931, 2161, 2243, 2707, 3863, 4211, 5227, 5669, 6551, 6703, 7537, 8167, 8231, 8663, 8941, 9067, 9497, 10651, 10789, 10861, 12619, 14033, 14173, 14431, 14639, 14797, 15187, 15497, 16223, 16703, 17609, 18457, 18481, 20261, 21313, 21803, 22133, 22247, 22279 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(3)=397 is in the sequence because it is prime, the next prime is 401, and 2*397^2-401^2 = 154417 and 2*401^2-397^2 = 163993 are prime.
MAPLE
N:= 100: # for the first N terms
q:= 2: count:= 0: R:= NULL:
for iter from 1 while count < N do
p:= q; q:= nextprime(q);
if isprime(2*p^2-q^2) and isprime(2*q^2-p^2) then
count:= count+1; R:= R, p;
fi
od:
R;
CROSSREFS
Sequence in context: A063363 A288619 A039476 * A061656 A141965 A141975
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Nov 11 2020
STATUS
approved

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Last modified April 12 14:01 EDT 2024. Contains 371635 sequences. (Running on oeis4.)