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A071808
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Smallest s such that sk+1 is squarefree for 1 <= k <= n.
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0
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1, 1, 2, 10, 10, 10, 10, 18, 18, 18, 18, 18, 18, 18, 18, 126, 126, 126, 126, 126, 126, 126, 126, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 270, 1470, 1470, 1470, 1890, 1890, 1890, 2310, 2310, 2310, 2310
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OFFSET
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1,3
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COMMENTS
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a(n)+1 or a(n)-1 is prime for listed terms.
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LINKS
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PROG
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(PARI) for(n=1, 57, s=1; while(sum(i=1, n, issquarefree(s*i+1))<n, 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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STATUS
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approved
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