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A075455
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Prime averages of two successive perfect powers (A001597(k) + A001597(k+1))/2.
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1
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2203, 77983, 90863, 185477, 371087, 388573, 613607, 912349, 1293899, 1600919, 2146457, 30661333, 35608189, 48823147, 81190429, 105823093, 122753857, 204341747, 338602837, 368601707, 374788121, 426958673, 498675409, 586371239, 656232799, 665360321, 674509487, 693132527
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OFFSET
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1,1
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LINKS
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EXAMPLE
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MATHEMATICA
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a = Select[Range[2, 50000000], GCD @@ (Transpose[FactorInteger[ # ]][[2]]) > 1 &]; sizea = Length[a]; (a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &]]] + a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &] + 1]])/2 (* Tanya Khovanova, Sep 15 2007 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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