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 A295101 Number of squarefree sqrt(n)-smooth numbers <= n. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS a(n) = number of positive squarefree integers m<=n such that A006530(m) <= sqrt(n). LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A013928(n+1) - Sum_{prime p > sqrt(n)} A013928(floor(n/p)+1). 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). MAPLE 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: convert(V, list); # Robert Israel, Mar 24 2020 CROSSREFS Cf. A005117, A013928, A295084. Sequence in context: A319799 A294078 A064133 * A160675 A105674 A130496 Adjacent sequences:  A295098 A295099 A295100 * A295102 A295103 A295104 KEYWORD nonn,look AUTHOR Max Alekseyev, Nov 14 2017 STATUS approved

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Last modified June 16 16:55 EDT 2021. Contains 345064 sequences. (Running on oeis4.)