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%I #37 Feb 12 2023 15:20:11
%S 7,23,31,47,71,79,103,127,151,167,191,199,223,239,263,271,311,359,367,
%T 383,431,439,463,479,487,503,599,607,631,647,719,727,743,751,823,839,
%U 863,887,911,919,967,983,991,1031,1039,1063,1087,1103,1151,1223,1231
%N Duplicate of A007522.
%C Original title was "Primes of the form -x^2 + 4xy + 4y^2 (as well as of the form 7x^2 + 12xy + 4y^2)."
%C _R. J. Mathar_ was the first to wonder if this entry is a duplicate. By elementary means, I very easily proved that all primes of this form are also of the form 8n + 7 (which is A007522). Then _Don Reble_ demonstrated that each prime of the form 8n + 7 has a corresponding representation as -x^2 + 4xy + 4y^2. Therefore the two sequences are in fact the same. - _Alonso del Arte_, Nov 21 2016
%K dead
%O 1,1
%A Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (oscfalgan(AT)yahoo.es), Jun 12 2008
%E More terms from _Colin Barker_, Apr 05 2015
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