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A257545
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a(0) = 2, a(n) = smallest prime p such that none of p - 1, p - 2,... p - n are squarefree.
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2
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2, 5, 29, 101, 5051, 5051, 73453, 671353, 130179187, 211014929, 262315477, 3639720053
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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a(3) = 101 because 101 is prime and none of 101 - 1 = 100, 101 - 2 = 99, and 101 - 3 = 98 are squarefree.
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MAPLE
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p:= 2:
A[0]:= 2:
m:= 0:
while p < 10^6 do
p:= nextprime(p);
for k from 1 while not numtheory:-issqrfree(p-k) do od:
if k > m+1 then
for j from m+1 to k-1 do A[j]:= p od:
m:= k-1;
fi
od:
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PROG
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(PARI) a(n)=forprime(p=2, , for(k=1, n, if(issquarefree(p-k), next(2))); return(p)) \\ Charles R Greathouse IV, Apr 29 2015
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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