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A130676 Numbers n for which either 16*n^2-6*n+1 or 16*n^2-10*n-1 or both is/are prime. 0

%I

%S 1,2,3,4,5,6,7,8,10,11,15,16,17,18,20,22,23,25,27,28,30,32,33,35,36,

%T 37,38,39,42,43,44,46,48,50,52,57,59,60,63,65,67,68,70,71,72,73,76,80,

%U 81,85,87,88,90,92,93,94,95,98,101,102,103,104,105,108,110,112,113,115,118,120,123,125,128,129,132,134

%N Numbers n for which either 16*n^2-6*n+1 or 16*n^2-10*n-1 or both is/are prime.

%C Consider the two forms (4*n-2)*4*n +- (2*n+1), where "+-" generates two different terms 16*n^2-6*n+1 and 16*n^2-10*n-1 for n=1,2,3,...

%C If at least one of the two numbers is prime, n is inserted into the sequence.

%e For n=20, 16*20^2 - 10*20 - 1= (4*20-2)*4*20-(2*20+1) = 6199 is prime, which adds 20 to the sequence.

%e For n=15, 16*15^2 - 6*15 +1= (4*15-2)*4*15 +(2*15+1) = 3511 is prime, which adds 15 to the sequence.

%K easy,nonn,less

%O 1,2

%A _J. M. Bergot_, Jun 28 2007

%E Edited and extended. - _R. J. Mathar_, Jul 10 2011

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Last modified May 14 16:48 EDT 2021. Contains 343898 sequences. (Running on oeis4.)