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A245482 Semiprimes of the form m^6 - m^5 + m^4 - m^3 + m^2 - m + 1. 1

%I #13 Aug 09 2014 23:04:07

%S 3277,13021,102943,233017,478297,2756293,44693587,465273397,705483871,

%T 859769191,2117950381,3996097561,8123248981,10554648343,11980986577,

%U 15318627451,21753909997,30299909641,33705129193,37423460467,41477524747,45891147541,97434620557,106376475037

%N Semiprimes of the form m^6 - m^5 + m^4 - m^3 + m^2 - m + 1.

%C All the terms in this sequence are odd semiprimes.

%C Primes of this form are at A245427.

%H K. D. Bajpai, <a href="/A245482/b245482.txt">Table of n, a(n) for n = 1..11040</a>

%e m = 4: m^6 - m^5 + m^4 - m^3 + m^2 - m + 1 = 3277 = 29 * 113, which is semiprime and appears in the sequence.

%e m = 5: m^6 - m^5 + m^4 - m^3 + m^2 - m + 1 = 13021 = 29 * 449, which is semiprime and appears in the sequence.

%t A245482 = {}; k = n^6 - n^5 + n^4 - n^3 + n^2 - n + 1; Do[If[PrimeOmega[k] == 2, AppendTo[A245482, k]], {n, 100}]; A245482

%o (PARI) for(n=1,100,s=sum(i=0,6,(-n)^i);if(bigomega(s)==2,print1(s,", "))) \\ _Derek Orr_, Jul 28 2014

%Y Cf. A001358, A162861, A245393, A245427.

%K nonn

%O 1,1

%A _K. D. Bajpai_, Jul 23 2014

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Last modified July 23 11:07 EDT 2024. Contains 374549 sequences. (Running on oeis4.)