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Number of primes less than n*10^11.
21

%I #20 Apr 03 2023 10:36:09

%S 4118054813,8007105059,11818439135,15581005657,19308136142,

%T 23007501786,26684074310,30341383527,33981987586,37607912018,

%U 41220703418,44821651132,48411812843,51992079337,55563209929,59125832286

%N Number of primes less than n*10^11.

%H Robert G. Wilson v, <a href="/A038820/b038820.txt">Table of n, a(n) for n = 1..10000</a>

%H Tomás Oliveira e Silva, <a href="http://sweet.ua.pt/tos/primes.html">Tables of values of pi(x) and of pi2(x)</a>

%H Andrew R. Booker, <a href="https://t5k.org/nthprime/">The Nth Prime Page</a>

%t Table[ PrimePi[ n*10^11 ], {n, 1, 18}]

%o (PARI) a(n)=primepi(10^11*n) \\ _Charles R Greathouse IV_, Apr 29 2015

%Y Cf. A038801, A028505, A038812, A038813, A038814, A038815, A038816, A038817, A038818, A038819, A038821, A080122, A080123, A080124, A080125, A080126, A080127, A080128, A080129.

%K nonn

%O 1,1

%A _Jeff Burch_

%E Edited and extended by _Robert G. Wilson v_, Jan 29 2003