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Values of n such that L(17) and N(17) are both prime, where L(k) = (n^2+n+1)*2^(2*k) + (2*n+1)*2^k + 1, N(k) = (n^2+n+1)*2^k + n.
1

%I #17 Mar 20 2019 12:27:35

%S 61,73,-135,-141,255,321,481,-767,-837,-1065,-1443,-1481,1579,1611,

%T -1689,1711,-1761,-1865,-1943,-2547,2577,-2753,-2831,-2981,-3209,

%U -3243,3445,-3543,-3735,3909,-4041,4219,4471,4549,-4587,-4791,-4833,-4853,-4875,4891,5071,-5259,-5379,5421,-5673,-5921,-5979,-6215,6529,-6689,-6773,-6897,6915,6943

%N Values of n such that L(17) and N(17) are both prime, where L(k) = (n^2+n+1)*2^(2*k) + (2*n+1)*2^k + 1, N(k) = (n^2+n+1)*2^k + n.

%C Computed with PARI using commands similar to those used to compute A226921.

%H Vincenzo Librandi and Joerg Arndt, <a href="/A227520/b227520.txt">Table of n, a(n) for n = 1..529</a>

%H Eric L. F. Roettger, <a href="http://people.ucalgary.ca/~hwilliam/files/A_Cubic_Extention_of_the_Lucas_Functions.pdf">A cubic extension of the Lucas functions</a>, Thesis, Dept. of Mathematics and Statistics, Univ. of Calgary, 2009. See page 195.

%Y Cf. A226921-A226929, A227448, A227449, A227515-A227523.

%K sign,easy

%O 1,1

%A _Vincenzo Librandi_, Jul 14 2013