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A218210
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Number of primes up to 10^n that are of the form (k-2)^2 + (k-1)^2 + k^2.
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4
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2, 3, 6, 10, 22, 53, 139, 369, 1050, 2984, 8618, 24390
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OFFSET
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1,1
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COMMENTS
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There are two primes < 10: 2 and 5.
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LINKS
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FORMULA
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MATHEMATICA
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n = -1; cnt = 0; Do[While[n++; p = 3*n^2 + 2; 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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