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%I #23 Feb 04 2024 09:03:55
%S 0,15,74,411,2447,16386,117207,879908,6849047,54818296,448725003,
%T 3741217498
%N Number of pairs (p,q) of (not necessarily consecutive) primes with q-p = 6 and q < 10^n.
%C Note that one has to be careful to distinguish between pairs of consecutive primes (p,q) with q-p = 6 (A031924), and pairs of primes (p,q) with q-p = 6 (A023201). Here we consider the latter, whereas A093738 considers the former. - _N. J. A. Sloane_, Mar 07 2021
%H A. Granville, G. Martin, <a href="http://www.dms.umontreal.ca/~andrew/PDF/PrimeRace.pdf">Prime number races</a>, Amer. Math. Monthly vol 113, no 1 (2006) p 1.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SexyPrimes.html">Sexy Primes</a>. [The definition in this webpage is unsatisfactory, because it defines a "sexy prime" as a pair of primes.- _N. J. A. Sloane_, Mar 07 2021].
%o (PARI) {c=0; p=7; for(n=1,9, while(p<10^n,if(isprime(p-6),c++); p=nextprime(p+1)); print1(c,","))}
%Y Cf. A023201, A046117, A007508, A080840, A006512, A046132, A046117.
%Y See also A031924, A093738.
%K nonn
%O 1,2
%A _Jason Earls_, Mar 28 2003
%E a(8) and a(9) from _Klaus Brockhaus_, Mar 30 2003
%E More terms from _R. J. Mathar_, Aug 05 2007
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