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 A137271 Numbers n such that pi(n^2)=pi((n-k)^2)+n, where k=A000193(n). 0
 2, 5, 14, 17, 18, 43, 44, 54, 107, 121, 137, 144, 417, 424, 868, 990, 991, 1094, 2529, 2586, 2740, 2741, 2785, 2878, 2948, 3085, 3176, 3267, 3269, 3346, 7319, 7694, 7750, 7868, 7984, 8061, 8161, 8250, 8308, 8340, 21182, 22190, 22801, 23200, 57448 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..45. MATHEMATICA Do[k=Round[Log[n]]; If[PrimePi[n^2]==PrimePi[(n-k)^2]+n, Print[n]], {n, 1, 10^5, 1}] CROSSREFS Cf. A000193, A000720. Sequence in context: A146526 A120626 A046058 * A131356 A191119 A089410 Adjacent sequences: A137268 A137269 A137270 * A137272 A137273 A137274 KEYWORD nonn AUTHOR Manuel Valdivia, Mar 13 2007 STATUS approved

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Last modified May 25 12:29 EDT 2024. Contains 372788 sequences. (Running on oeis4.)