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A080841
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Number of sexy primes < 10^n.
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1
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0, 15, 74, 411, 2447, 16386, 117207, 879908, 6849047, 54818296, 448725003, 3741217498
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| The corresponding numbers for twin primes and cousin primes are in A007508 and A080840, the greater of twin primes, cousin primes and sexy primes are in A006512, A046132 and A046117 respectively.
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LINKS
| Eric Weisstein's World of Mathematics, Sexy Primes.
A. Granville, G. Martin, Prime number races, Amer. Math. Monthly vol 113, no 1 (2006) p 1.
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PROG
| (PARI) {c=0; p=7; for(n=1, 9, while(p<10^n, if(isprime(p-6), c++); p=nextprime(p+1)); print1(c, ", "))}
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CROSSREFS
| Cf. A023201, A046117.
Cf. A007508, A080840, A006512, A046132, A046117.
Sequence in context: A002603 A022817 A171341 * A022675 A135916 A051880
Adjacent sequences: A080838 A080839 A080840 * A080842 A080843 A080844
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KEYWORD
| nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Mar 28 2003
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EXTENSIONS
| a(8) and a(9) from Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Mar 30 2003
More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 05 2007
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