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A068231 Primes congruent to 11 mod 12.

%I A068231 #48 Sep 15 2023 16:34:19
%S A068231 11,23,47,59,71,83,107,131,167,179,191,227,239,251,263,311,347,359,
%T A068231 383,419,431,443,467,479,491,503,563,587,599,647,659,683,719,743,827,
%U A068231 839,863,887,911,947,971,983,1019,1031,1091,1103,1151,1163,1187,1223
%N A068231 Primes congruent to 11 mod 12.
%C A068231 Intersection of A002145 (primes of form 4n+3) and A003627 (primes of form 3n-1). So these are both Gaussian primes with no imaginary part and Eisenstein primes with no imaginary part. - _Alonso del Arte_, Mar 29 2007
%C A068231 Is this the same sequence as A141187 (apart from the initial 3)?
%C A068231 If p is prime of the form 2*a(n)^k + 1, then p divides a cyclotomic number Phi(a(n)^k, 2). - _Arkadiusz Wesolowski_, Jun 14 2013
%C A068231 Also a(n) = primes p dividing A014138((p-3)/2), where A014138(n) = Partial sums of (Catalan numbers starting 1,2,5,...), cf. A000108. - _Alexander Adamchuk_, Dec 27 2013
%H A068231 Vincenzo Librandi, <a href="/A068231/b068231.txt">Table of n, a(n) for n = 1..1000</a>
%t A068231 Select[Prime/@Range[250], Mod[ #, 12]==11&]
%t A068231 Select[Range[11,1500,12],PrimeQ] (* _Harvey P. Dale_, Sep 15 2023 *)
%o A068231 (PARI) for(i=1,250, if(prime(i)%12==11, print(prime(i))))
%o A068231 (Magma) [p: p in PrimesUpTo(1500) | p mod 12 eq 11 ]; // _Vincenzo Librandi_, Aug 14 2012
%o A068231 (MATLAB)
%o A068231 %4n-1 and 6n-1 primes
%o A068231 n = 1:10000;
%o A068231 n2 = 4*n-1;
%o A068231 n3 = 3*n-1;
%o A068231 p = primes(max(n2));
%o A068231 Res = intersect(n2,n3);
%o A068231 Res2 = intersect(Res,p);
%o A068231 % _Jesse H. Crotts_, Sep 25 2016
%Y A068231 Cf. A068227, A068228, A068229, A040117, A068232, A068233, A068234, A068235, A000040, A014138, A000108.
%K A068231 easy,nonn
%O A068231 1,1
%A A068231 Ferenc Adorjan (fadorjan(AT)freemail.hu), Feb 22 2002
%E A068231 Edited by _Dean Hickerson_, Feb 27 2002