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A087373
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Twin-prime-indexed primes (TWIPS): members of a pair of twin primes whose prime index is also a member of a pair of twin primes.
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1
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5, 11, 17, 31, 41, 59, 109, 179, 191, 283, 599, 859, 1063, 1153, 1723, 2081, 2341, 3001, 3259, 3299, 4421, 4549, 4787, 4933, 6361, 6661, 8221, 8233, 8389, 10009, 10457, 10861, 13693, 13709, 16141, 16693, 16901, 17387, 17659, 20441, 20477, 20773
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OFFSET
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1,1
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COMMENTS
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If there are infinitely many twin primes, this sequence has an infinite number of terms.
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LINKS
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EXAMPLE
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17 is a twin prime paired with 19. The 17th prime is 59 which is also a twin prime paired with 61.
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PROG
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(PARI) twips(n) = { forprime(x=3, n, x1=prime(x); if(isprime(x-2) || isprime(x+2), if(isprime(x1-2) || isprime(x1+2), print1(x1", ") ) ) ) }
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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