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A340307
Primes of the form (p*q+r*s)/2, where p,q,r,s are consecutive primes.
2
89, 149, 233, 907, 3607, 6577, 13007, 20771, 27241, 34631, 72907, 84737, 110933, 145177, 213449, 360007, 463787, 680633, 746507, 1192469, 1695209, 2205233, 2643899, 3125959, 3261721, 4888547, 4995227, 5716897, 6095987, 6656483, 7225349, 7734029, 7868027, 7969439, 8071307, 11189053, 11329991
OFFSET
1,1
LINKS
EXAMPLE
a(3) = 233 is a term because 233 = (11*13+17*19)/2.
MAPLE
q:= 3: r:= 5: s:= 7:
count:= 0: R:= NULL:
while count < 100 do
p:= q; q:= r; r:= s; s:= nextprime(s);
v:= (p*q + r*s)/2;
if isprime(v) then count:= count+1; R:= R, v fi
od:
R;
CROSSREFS
Cf. A340308.
Sequence in context: A141938 A267819 A031416 * A353249 A247114 A075589
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Jan 03 2021
STATUS
approved