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A085701
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Smallest multiple of n such that a(n) + a(n-1) is a squarefree number.
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0
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1, 2, 3, 4, 10, 12, 7, 8, 9, 10, 11, 12, 26, 56, 15, 16, 17, 18, 19, 20, 21, 22, 69, 24, 50, 52, 27, 28, 29, 30, 31, 64, 33, 34, 35, 36, 37, 76, 39, 40, 82, 84, 43, 44, 45, 46, 47, 48, 49, 100, 51, 52, 53, 54, 55, 56, 57, 58, 177, 60, 122, 124, 63, 64, 65, 66, 67, 136, 69, 70, 71
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OFFSET
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1,2
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COMMENTS
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The sequence ends with a(319)=1276, since 320k + 1276 is divisible by 4 for all k.
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LINKS
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MATHEMATICA
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smn[{n_, a_}]:=Module[{k=1}, While[!SquareFreeQ[a+k*n], k++]; {n+1, k*n}]; NestList[ smn, {1, 1}, 80][[All, 2]] (* Harvey P. Dale, Jul 02 2022 *)
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CROSSREFS
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KEYWORD
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fini,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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