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A138655
Primes p such that 36*p-1 and 36*p+1 are twin primes.
1
2, 3, 5, 23, 107, 137, 157, 163, 193, 233, 457, 577, 647, 677, 857, 1013, 1123, 1223, 1237, 1783, 1867, 1873, 2243, 2417, 2467, 2683, 2957, 3407, 3413, 3517, 3797, 4373, 4447, 4603, 4903, 5413, 5437, 5813, 6053, 6073, 6323, 6577, 6823, 6863, 7207, 7793
OFFSET
1,1
LINKS
EXAMPLE
36*2-1=71, 36*2+1=73; 36*3-1=107, 36*p+1=109;...
MAPLE
Res:= NULL: count:= 0:
p:= 1:
while count < 100 do
p:= nextprime(p);
if isprime(36*p-1) and isprime(36*p+1) then
count:= count+1; Res:= Res, p;
fi
od:
Res; # Robert Israel, Jan 14 2019
MATHEMATICA
a=36; Select[Prime[Range[10^3]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&]
CROSSREFS
Sequence in context: A182976 A042363 A208220 * A053708 A137070 A084730
KEYWORD
nonn
AUTHOR
STATUS
approved