OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= proc(n)
if not isprime(n) then return false fi;
if n mod 3 = 1 then isprime(n-2) else isprime(n+2) fi
end proc:
select(filter, [seq(i, i=9..10^4, 10)]); # Robert Israel, Nov 19 2023
MATHEMATICA
Select[Prime@ Range@ 800, Mod[ #, 10] == 9 && (PrimeQ[ # - 2] || PrimeQ[ # + 2]) &] (* Robert G. Wilson v, Nov 06 2010 *)
Select[Union[Flatten[Select[Partition[Prime[Range[400]], 2, 1], #[[2]]-#[[1]]==2&]]], Mod[#, 10]==9&] (* Harvey P. Dale, May 21 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Nov 01 2010
EXTENSIONS
More terms from Robert G. Wilson v, Nov 06 2010
STATUS
approved