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A295101
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Number of squarefree sqrt(n)-smooth numbers <= n.
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3
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1, 1, 1, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14
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OFFSET
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1,4
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COMMENTS
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a(n) = number of positive squarefree integers m<=n such that A006530(m) <= sqrt(n).
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LINKS
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FORMULA
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If n is in A295102, then a(n)=a(n-1)+1; if n is in A001248, i.e., n=p^2 for prime p, then a(n)=a(n-1)+A013928(p); otherwise a(n)=a(n-1).
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MAPLE
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N:= 200: # for a(1)..a(N)
V:= Vector(N, 1):
for n from 2 to N do
if not numtheory:-issqrfree(n) then next fi;
m:= max(max(numtheory:-factorset(n))^2, n);
if m <= N then V[m..N]:= map(`+`, V[m..N], 1) fi;
od:
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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