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A322493
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Start of first occurrence of n consecutive odd squarefree composite numbers.
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1
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OFFSET
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1,1
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COMMENTS
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The sequence is finite because among 9 or more consecutive odd numbers there is always a multiple of 3*3. - Rémy Sigrist, Dec 19 2018
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LINKS
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EXAMPLE
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a(2) = 33 because 33 = 3*11 and 35 = 5*7 is the smallest pair of odd squarefree composite numbers. 31 and 37 are prime.
a(8) = 1343: 1343=17*79, 1345=5*269, 1347=3*449, 1349=19*71, 1351=7*193, 1353=3*11*41, 1355=5*271, 1357=23*59, whereas 1341=3^2*149 and 1359=3^2*151 are not squarefree.
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MATHEMATICA
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a[n_] := For[k = 1, True, k = k+2, If[AllTrue[Range[k, k+2(n-1), 2], CompositeQ[#] && SquareFreeQ[#]&], Return[k]]];
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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