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A275381
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Number of prime factors (with multiplicity) of generalized Fermat number 10^(2^n) + 1.
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2
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OFFSET
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0,3
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LINKS
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Table of n, a(n) for n=0..8.
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FORMULA
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a(n) = A001222(A080176(n)). - Felix Fröhlich, Jul 25 2016
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EXAMPLE
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b(n) = 10^(2^n) + 1.
Complete Factorizations
b(0) = 11
b(1) = 101
b(2) = 73*137
b(3) = 17*5882353
b(4) = 353*449*641*1409*69857
b(5) = 19841*976193*6187457*834427406578561
b(6) = 1265011073*
15343168188889137818369*515217525265213267447869906815873
b(7) = 257*15361*453377*P116
b(8) = 10753*8253953*9524994049*73171503617*P225
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MATHEMATICA
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Table[PrimeOmega[10^(2^n) + 1], {n, 0, 6}] (* Michael De Vlieger, Jul 26 2016 *)
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PROG
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(PARI) a(n) = bigomega(factor(10^(2^n)+1))
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CROSSREFS
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Cf. A072982, A080176.
Sequence in context: A217876 A209771 A209751 * A283235 A209763 A209761
Adjacent sequences: A275378 A275379 A275380 * A275382 A275383 A275384
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KEYWORD
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nonn,hard,more
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AUTHOR
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Arkadiusz Wesolowski, Jul 25 2016
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STATUS
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approved
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