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A218208
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Number of primes up to 10^n that are of the form (k-1)^2 + k^2.
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4
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1, 4, 10, 26, 68, 175, 461, 1225, 3349, 9266, 26516, 76334, 221763
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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n = 0; cnt = 0; Table[While[n++; p = 2*n^2 - 2*n + 1; p < 10^e, If[PrimeQ[p], cnt++]]; n--; cnt, {e, 10}] (* T. D. Noe, Oct 23 2012 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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