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 A218210 Number of primes up to 10^n that are of the form (k-2)^2 + (k-1)^2 + k^2. 4
 2, 3, 6, 10, 22, 53, 139, 369, 1050, 2984, 8618, 24390 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are two primes < 10: 2 and 5. LINKS FORMULA a(n) = sum(A218209(k), k=1..n) MATHEMATICA 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 *) CROSSREFS Cf. A027863, A027864, A218208, A218209, A218212. Sequence in context: A156803 A002992 A130867 * A122381 A141034 A300442 Adjacent sequences:  A218207 A218208 A218209 * A218211 A218212 A218213 KEYWORD nonn,base AUTHOR Martin Renner, Oct 23 2012 STATUS approved

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Last modified April 7 01:11 EDT 2020. Contains 333291 sequences. (Running on oeis4.)