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A050264
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Weak veryprimes.
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1
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2, 3, 5, 7, 11, 13, 17, 19, 23, 37, 43, 47, 53, 67, 73, 103, 107, 137, 157, 173, 227, 347, 487, 773
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Eric Weisstein's World of Mathematics, Veryprime
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MATHEMATICA
| veryprimeQ[n_] := (p = 2; r = True; While[p <= Sqrt[n], If[Abs[2*Mod[n, p] - p] > p/2, r = False; Break[]]; p = NextPrime[p]]; r); Select[ Prime[ Range[10000]], veryprimeQ](* From Jean-François Alcover, Nov 30 2011 *)
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PROG
| (Haskell)
a050264 n = a050264_list !! (n-1)
a050264_list = filter chi [2..] where
chi n = f a000040_list where
f (p:ps) | p*p > n = True
| otherwise = 2 * abs (2 * (n `mod` p) - p) <= p && f ps
-- Reinhard Zumkeller, Aug 11 2011
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CROSSREFS
| Sequence in context: A046501 A033875 A105581 * A075239 A008792 A094746
Adjacent sequences: A050261 A050262 A050263 * A050265 A050266 A050267
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KEYWORD
| nonn,nice
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AUTHOR
| Eric Weisstein (eric(AT)weisstein.com), Jim Ferry (jferry(AT)uiuc.edu)
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EXTENSIONS
| No others in first 100000 primes.
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