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%I #58 Dec 07 2022 13:02:15
%S 7,19,31,43,67,79,103,127,139,151,163,199,211,223,271,283,307,331,367,
%T 379,439,463,487,499,523,547,571,607,619,631,643,691,727,739,751,787,
%U 811,823,859,883,907,919,967,991,1039,1051,1063,1087,1123,1171,1231
%N Primes congruent to 7 (mod 12).
%C Primes of the form 3x^2 + 4y^2. - _T. D. Noe_, May 08 2005
%C It appears that all terms starting from term 103 are primes which are the sum of 5 positive (n > 0) different squares in more than one way (A193143) - _Vladimir Joseph Stephan Orlovsky_, Jul 16 2011.
%H Vincenzo Librandi, <a href="/A068229/b068229.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ 4n log n. - _Charles R Greathouse IV_, Dec 07 2022
%t Select[Prime/@Range[250], Mod[#, 12] == 7 &]
%o (PARI) for(i=1,250, if(prime(i)%12==7, print(prime(i))))
%o (Magma) [ p: p in PrimesUpTo(1400) | p mod 12 in {7} ]; // _Vincenzo Librandi_, Jul 14 2012
%o (PARI) is_A068229(n)=n%12==7 && isprime(n) \\ then, e.g.,
%o select(is_A068229, primes(250)) \\ - _M. F. Hasler_, Jan 25 2013
%Y Cf. A068227, A068228, A040117, A068231, A068232, A068233, A068234, A068235.
%K easy,nonn
%O 1,1
%A Ferenc Adorjan (fadorjan(AT)freemail.hu), Feb 22 2002
%E Edited by _Dean Hickerson_, Feb 27 2002
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