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A181604
Twin primes ending in 3.
4
3, 13, 43, 73, 103, 193, 283, 313, 433, 463, 523, 643, 823, 883, 1033, 1063, 1093, 1153, 1303, 1453, 1483, 1723, 1873, 1933, 2083, 2113, 2143, 2383, 2593, 2713, 2803, 3253, 3373, 3463, 3583, 3673, 3823, 3853, 4003, 4093, 4243, 4273, 4423, 4483, 4723, 4933
OFFSET
1,1
MAPLE
isA181604 := proc(p)
if isprime(p) and (isprime(p-2) or isprime(p+2)) then
if modp(p, 10) = 3 then
true;
else
false;
end if ;
else
false;
end if;
end proc: # R. J. Mathar, Feb 14 2017
MATHEMATICA
Select[Prime@Range@700, Mod[ #, 10] == 3 && (PrimeQ[ # - 2] || PrimeQ[ # + 2]) &] (* Robert G. Wilson v, Nov 06 2010 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Omar E. Pol, Nov 01 2010
EXTENSIONS
More terms from Robert G. Wilson v, Nov 06 2010
STATUS
approved