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A245482
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Semiprimes of the form m^6 - m^5 + m^4 - m^3 + m^2 - m + 1.
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1
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3277, 13021, 102943, 233017, 478297, 2756293, 44693587, 465273397, 705483871, 859769191, 2117950381, 3996097561, 8123248981, 10554648343, 11980986577, 15318627451, 21753909997, 30299909641, 33705129193, 37423460467, 41477524747, 45891147541, 97434620557, 106376475037
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OFFSET
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1,1
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COMMENTS
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All the terms in this sequence are odd semiprimes.
Primes of this form are at A245427.
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LINKS
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EXAMPLE
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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.
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.
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MATHEMATICA
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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
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PROG
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(PARI) for(n=1, 100, s=sum(i=0, 6, (-n)^i); if(bigomega(s)==2, print1(s, ", "))) \\ Derek Orr, Jul 28 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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