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 A053671 Least number coprime to n, n+1 and n+2. 2
 5, 5, 7, 7, 11, 5, 5, 7, 7, 7, 5, 5, 11, 11, 7, 5, 5, 7, 11, 13, 5, 5, 7, 7, 7, 5, 5, 11, 7, 7, 5, 5, 13, 11, 11, 5, 5, 7, 7, 11, 5, 5, 7, 7, 7, 5, 5, 11, 11, 7, 5, 5, 7, 13, 13, 5, 5, 7, 7, 7, 5, 5, 11, 7, 7, 5, 5, 11, 11, 11, 5, 5, 7, 7, 13, 5, 5, 7, 7, 7, 5, 5, 11, 11, 7, 5, 5, 7, 11, 11, 5, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MATHEMATICA a[n_] := (k = 5; While[! (CoprimeQ[k, n] && CoprimeQ[k, n+1] && CoprimeQ[k, n+2]), k++]; k); Table[a[n], {n, 1, 92}] (* Jean-François Alcover, Nov 30 2011 *) lnc[n_]:=Module[{k=5, c=n+{0, 1, 2}}, While[!And@@CoprimeQ[k, c], k=k+2]; k]; Array[lnc, 100] (* Harvey P. Dale, Mar 01 2015 *) PROG (Haskell) a053671 n = f \$ drop 2 a000040_list where    f (p:ps) | (n `mod` p) * ((n+1) `mod` p) * ((n+2) `mod` p) > 0 = p             | otherwise = f ps -- Reinhard Zumkeller, Mar 19 2011 CROSSREFS Cf. A053669-A053674. Sequence in context: A244587 A111186 A127798 * A028278 A095943 A120220 Adjacent sequences:  A053668 A053669 A053670 * A053672 A053673 A053674 KEYWORD nonn,easy,nice AUTHOR Henry Bottomley, Feb 15 2000 EXTENSIONS More terms from James A. Sellers, Feb 22 2000 STATUS approved

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Last modified April 19 11:13 EDT 2019. Contains 322263 sequences. (Running on oeis4.)