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A071568
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Smallest k>n such that n^3+1 divides k*n^2+1.
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9
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1, 3, 11, 31, 69, 131, 223, 351, 521, 739, 1011, 1343, 1741, 2211, 2759, 3391, 4113, 4931, 5851, 6879, 8021, 9283, 10671, 12191, 13849, 15651, 17603, 19711, 21981, 24419, 27031, 29823, 32801, 35971, 39339, 42911, 46693, 50691, 54911, 59359
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = n^3+n+1.
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MATHEMATICA
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sk[n_]:=Module[{k=n+1, n2=n^2, n3=n^3+1}, While[!Divisible[k*n2+1, n3], k++]; k]; Array[sk, 40] (* Harvey P. Dale, Jun 13 2013 *)
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PROG
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(PARI) for(n=1, 50, s=n+1; while((s*n^2+1)%(n^3+1)>0, s++); print1(s, ", "))
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CROSSREFS
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KEYWORD
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easy,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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