

A057752


Difference between nearest integer to Li(10^n) and pi(10^n), where Li(x) = integral of log(x) and pi(10^n) = number of primes <= 10^n (A006880).


10



2, 5, 10, 17, 38, 130, 339, 754, 1701, 3104, 11588, 38263, 108971, 314890, 1052619, 3214632, 7956589, 21949555, 99877775, 222744644, 597394254, 1932355208, 7250186216, 17146907278, 55160980939, 155891678121, 508666658006
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

On his prime pages C. K. Caldwell remarks: "However in 1914 Littlewood proved that pi(x)Li(x) assumes both positive and negative values infinitely often".  Frank Ellermann, May 31 2003


REFERENCES

John H. Conway and R. K. Guy, The Book of Numbers, Copernicus, an imprint of SpringerVerlag, NY, 1995, page 146.
Marcus du Sautoy, The Music of the Primes, Fourth Estate / HarperCollins, 2003; see table on p. 90.


LINKS

Table of n, a(n) for n=1..27.
Chris K. Caldwell, How many primes are there, table, Values of pi(x).
Chris K. Caldwell, How many primes are there, table, Approximations to pi(x).
Xavier Gourdon & Pascal Sebah, Counting the primes
Andrew Granville, Harald Cramer and the Distribution of Prime Numbers
Anatolii A. Karatsuba and Ekatherina A. Karatsuba, The "problem of remainders" in theoretical physics: "physical zeta" function, 6th Mathematical Physics Meeting: Summer School and Conference on Modern Mathematical Physics, 1423 September 2010, Belgrade, Serbia. [From Internet Archive Wayback Machine]
Tomás Oliveira e Silva, Tables of values of pi(x) and of pi2(x)
Y. Saouter, P. Demichel, A sharp region where pi(x)li(x) is positive, Math. Comp. 79 (272) (2010) 23952405. [From R. J. Mathar, Oct 08 2010]
Munibah Tahir, A new bound for the smallest x with pi(x) > li(x) (2010)
Eric Weisstein's World of Mathematics, Prime Counting Function
Wikipedia, Prime number theorem


MATHEMATICA

Table[Round[LogIntegral[10^n]  PrimePi[10^n]], {n, 1, 13}]


PROG

(PARI) A057752=vector(#A006880, i, round(eint1(log(10^i))A006880[i])) \\ M. F. Hasler, Feb 26 2008
(Python)
from sympy import N, li, primepi, floor
def round(n):
return int(floor(n+0.5))
def A057752(n):
return round(N(li(10**n), 10*n))  primepi(10**n) # Chai Wah Wu, Apr 30 2018


CROSSREFS

Cf. A006880, A052435, A057794.
Sequence in context: A018315 A146220 A054964 * A173057 A213299 A172114
Adjacent sequences: A057749 A057750 A057751 * A057753 A057754 A057755


KEYWORD

sign,hard


AUTHOR

Robert G. Wilson v, Oct 30 2000


EXTENSIONS

More terms from Frank Ellermann, May 31 2003
The value of a(23) is not known at present, I believe.  N. J. A. Sloane, Mar 17 2008
Name corrected and extended for last two terms a(23) and a(24), with Pi(10^n) for n=23 and 24 from A006880, by Vladimir Pletser, Mar 10 2013
Added a(25)a(27) using data from A006880, by Chai Wah Wu, Apr 30 2018


STATUS

approved



