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A141755
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Product of two primes whose sum is a perfect square.
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1
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4, 14, 39, 46, 55, 94, 155, 158, 183, 203, 291, 295, 299, 323, 334, 446, 579, 583, 695, 718, 799, 878, 943, 955, 959, 979, 1191, 1255, 1411, 1454, 1678, 1703, 2019, 2059, 2159, 2174, 2219, 2395, 2419, 2446, 2491, 2734, 2855, 3043, 3063, 3443, 3459, 3503, 3694
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..49.
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MATHEMATICA
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Take[ Sort[ Times @@@ Select[ Subsets[ Array[ Prime, 290], {2}], IntegerQ[ Sqrt[ #[[2]] + #[[1]]]] &]], 48]
nn=4000; fQ[n_] := Module[{p, e}, If[n < 2, False, {p, e} = Transpose[FactorInteger[n]]; If[Total[e] != 2, False, IntegerQ[Sqrt[Total[p*e]]]]]]; Select[Range[nn], fQ] (* T. D. Noe, Mar 22 2012 *)
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CROSSREFS
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Cf. A000040, A000290, A143416.
Sequence in context: A111583 A124615 A114845 * A064463 A130423 A055484
Adjacent sequences: A141752 A141753 A141754 * A141756 A141757 A141758
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KEYWORD
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nonn
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AUTHOR
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David Spector (spectord(AT)ccsu.edu) and Robert G. Wilson v, Aug 31 2008
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STATUS
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approved
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