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A085745
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Numbers m such that 2^m + m is a semiprime.
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4
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2, 11, 23, 34, 59, 69, 87, 95, 119, 123, 129, 171, 197, 239, 341, 425, 455, 471, 515, 519, 635, 765, 959, 1115, 1181, 1210
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = 2*k <=> A089535(n) is even <=> A089536(n) = 2 <=> A089537(n) = 4^k/2 + k, and for any prime of this form, there is a term a(n) = 2*k in this sequence. - M. F. Hasler, Oct 08 2009
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MATHEMATICA
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Select[Range[1300], PrimeOmega[2^#+#]==2&] (* Harvey P. Dale, Dec 18 2014 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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