Search: id:A065421 Results 1-1 of 1 results found. %I A065421 %S A065421 1,9,0,2,1,6,0,5,8,3,1,0,4 %N A065421 Decimal expansion of Viggo Brun's constant B, also known as the twin primes Brun's constant B_2: Sum (1/p + 1/q) as (p,q) runs through the twin primes. %C A065421 Another constant related to the twin primes is the twin primes constant C_2 (sometimes also denoted PI_2) A005597 defined in connection with the Hardy-Littlewood conjecture concerning the distribution pi_2(x) of the twin primes. %D A065421 V. Brun, La serie 1/5 + 1/7 + 1/11 + 1/13 + 1/17 + 1/19 + 1/29 + 1/31 + 1/41 + 1/43 + 1/59 + 1/61 + ... ou les denominateurs sont "nombres premiers jumeaux" est convergente ou finie, Bull Sci. Math. 43 (1919) 100-104 and 124-128. %D A065421 R. Crandall and C. Pomerance, Prime Numbers: A Computational Perspective, Springer, NY, 2001; see p. 14. %D A065421 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 133-135. %D A065421 D. Shanks and J. W. Wrench, Brun's constant, Math. Comp. 28 (1974) 293-299; 28 (1974) 1183; Math. Rev. 50 #4510. %H A065421 C. K. Caldwell, The Prime Glossary, Brun's constant %H A065421 S. R. Finch, Brun's Constant %H A065421 P. Sebah, Numbers, constants and computation %H A065421 T. R. Nicely, Enumeration to 10^14 of the twin primes and Brun's constant. %H A065421 T. R. Nicely, Prime Constellations Research Project %H A065421 Wikipedia, Brun's constant %F A065421 (1/3+1/5) + (1/5+1/7) + (1/11+1/13) + ... %e A065421 1.902160583190 +- 0.000000001175 [Nicely] %Y A065421 Cf. A005597 Decimal expansion of twin prime constant C_2 = Product_{ p prime >= 3 } (1-1/(p-1)^2). %Y A065421 Sequence in context: A013570 A065471 A089481 this_sequence A093767 A107091 A153790 %Y A065421 Adjacent sequences: A065418 A065419 A065420 this_sequence A065422 A065423 A065424 %K A065421 hard,nonn,cons,nice %O A065421 1,2 %A A065421 Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 08 2000 %E A065421 Corrected by N. J. A. Sloane (njas(AT)research.att.com), Nov 16, 2001 %E A065421 More terms computed by Pascal Sebah (pascal_sebah(AT)ds-fr.com), Jul 15, 2001 %E A065421 Further terms computed by Pascal Sebah (psebah(AT)yahoo.fr), Aug 22 2002 %E A065421 Commented and edited by Daniel Forgues (squid(AT)zensearch.com), Jul 28 2009 Search completed in 0.001 seconds