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A087243
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a(n)=n+A0876242(n) or a(n)=0 if A087242(n)=0; the primes arising as n+A087642(n).
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2
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3, 5, 5, 7, 7, 11, 0, 11, 11, 13, 13, 17, 0, 17, 17, 19, 19, 23, 0, 23, 23, 29, 0, 29, 0, 29, 29, 31, 31, 37, 0, 37, 0, 37, 37, 41, 0, 41, 41, 43, 43, 47, 0, 47, 47, 53, 0, 53, 0, 53, 53, 59, 0, 59, 0, 59, 59, 61, 61, 67, 0, 67, 0, 67, 67, 71, 0, 71, 71, 73, 73, 79, 0, 79, 0, 79, 79, 83, 0
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| a(n)=n+Min{x; n+x is prime} or a(n)=0 if Min{} exists.
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EXAMPLE
| a(n)=0, i.e. no solution exists if n is a special
prime, namely n is not a lesser-twin-prime;
e.g. if n=7, then neither 7+2=9 nor 7+(oddprime) is a prime, thus
no p prime exits such that 7+p was also a prime.
If n=lesser-twin-prime then a(n)=2 is a solution because
n+a[n]=n+2=larger-twin-prime satisfying condition.
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CROSSREFS
| Cf. A087243.
Sequence in context: A103332 A195796 A079886 * A112276 A079578 A066169
Adjacent sequences: A087240 A087241 A087242 * A087244 A087245 A087246
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Sep 04 2003
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