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A133228 Number of primes < square root of n!. 10

%I

%S 0,0,1,2,4,9,19,46,110,291,822,2455,7740,25635,88849,320749,1202674,

%T 4670156,18741145,77553119,330321299,1445829174,6493985903,

%U 29891948760,140843699641,678576973614,3339785593878

%N Number of primes < square root of n!.

%t Table[PrimePi[Sqrt[n! ]], {n, 27}] (* _Robert G. Wilson v_ *)

%o (PARI) a(n)=primepi(sqrtint(n!)) \\ _Charles R Greathouse IV_, Sep 15 2015

%Y Cf. A003604.

%K nonn

%O 1,4

%A _Giovanni Teofilatto_, Oct 13 2007

%E More terms from _Stefan Steinerberger_ and _Robert G. Wilson v_, Oct 14 2007

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Last modified May 16 01:48 EDT 2021. Contains 343937 sequences. (Running on oeis4.)