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A342508
Primes p such that (q*r-p*s)/2 is prime, where p,q,r,s are consecutive primes.
5
211, 773, 797, 929, 1733, 2113, 2417, 2531, 2621, 2663, 2671, 3041, 3307, 3491, 3499, 4099, 4397, 4423, 4567, 4583, 4987, 5483, 5743, 6101, 6841, 6899, 7187, 7309, 7417, 7529, 9649, 10103, 10463, 10501, 10607, 10631, 10651, 11003, 11119, 11833, 11941, 12479, 12763, 12967, 13163, 13697, 14449
OFFSET
1,1
LINKS
EXAMPLE
a(3) = 797 is a term because 797, 809, 811, 821 are consecutive primes with (809*811-797*821)/2 = 881 prime.
MAPLE
R:= NULL: count:= 0:
q:= 3: r:= 5: s:= 7:
while count < 100 do
p:= q; q:= r; r:= s; s:= nextprime(s);
if isprime((q*r-p*s)/2) then
count:= count+1; R:= R, p;
fi
od:
R;
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Mar 14 2021
STATUS
approved