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A214060
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Least m>0 such that gcd(2*n-1+m, n-m) > 1.
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2
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1, 2, 1, 4, 1, 6, 1, 8, 1, 10, 1, 2, 1, 14, 1, 16, 1, 18, 1, 20, 1, 2, 1, 24, 1, 4, 1, 28, 1, 30, 1, 2, 1, 34, 1, 36, 1, 38, 1, 5, 1, 2, 1, 44, 1, 46, 1, 4, 1, 50, 1, 2, 1, 5, 1, 56, 1, 58, 1, 60, 1, 2, 1, 64, 1, 66, 1, 5, 1, 4, 1, 2, 1, 6, 1, 76, 1, 78, 1, 80, 1, 2, 1, 84, 1, 86, 1
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OFFSET
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1,2
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LINKS
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EXAMPLE
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gcd(23+1,12-1) = 1 and gcd(23+2,12-2) > 1, so that a(12) = 2.
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MATHEMATICA
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b[n_] := 2*n - 1; c[n_] := n;
Table[m = 1; While[GCD[b[n] + m, c[n] - m] == 1, m++]; m, {n, 1, 150}]
lmg[n_]:=Module[{m=1}, While[GCD[2n-1+m, n-m]<2, m++]; m]; Array[lmg, 90] (* Harvey P. Dale, Jan 14 2020 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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