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A080191
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Primes p such that p is the largest of all prime factors of the numbers between the prime preceding 2*p and the next prime.
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2
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2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 61, 67, 73, 79, 83, 89, 97, 103, 109, 113, 127, 131, 137, 139, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 269, 271, 277, 281, 283, 293, 307, 313
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Complement of A080192 relative to A000040.
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FORMULA
| f(precprime(2*p)) = p, where f is the mapping defined by A052248.
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EXAMPLE
| 5 is a term since 7 is the prime preceding 2*5, 11 is the next prime and 5 is the largest of all prime factors of 8, 9 and 10.
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PROG
| (PARI) {forprime(k=2, 317, p=precprime(2*k); q=nextprime(p+1); m=0; for(j=p+1, q-1, f=factor(j); a=f[matsize(f)[1], 1]; if(m<a, m=a)); if(m==k, print1(k, ", ")))}
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CROSSREFS
| Cf. A000040, A080192, A052248.
Sequence in context: A050246 A118849 A049561 * A073350 A167773 A049545
Adjacent sequences: A080188 A080189 A080190 * A080192 A080193 A080194
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KEYWORD
| nonn
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AUTHOR
| Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Feb 10 2003
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