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A117328
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Primes p such that p+/-4 are semiprimes.
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2
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29, 53, 61, 73, 89, 137, 173, 181, 263, 331, 449, 523, 541, 547, 569, 577, 587, 593, 683, 691, 727, 811, 839, 947, 1051, 1063, 1153, 1163, 1223, 1259, 1289, 1367, 1531, 1559, 1627, 1637, 1847, 1861, 1933, 1973, 1987, 2099, 2153, 2161, 2213, 2267, 2287, 2311
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Cf. A063643 Primes p such that p+/-2 are semiprimes.
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EXAMPLE
| 29-4=25=5*5 (semiprime). 29+4=33=3*11 (semiprime).
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MATHEMATICA
| fQ[n_] := Plus @@ Last /@ FactorInteger@n == 2; Select[ Prime@ Range[3, 345], fQ[ # - 4] && fQ[ # + 4] &] (from Robert G. Wilson v (rgwv(at)rgwv.com), May 01 2006)
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CROSSREFS
| Cf. A063643.
Sequence in context: A042947 A134555 A164075 * A105406 A124284 A054822
Adjacent sequences: A117325 A117326 A117327 * A117329 A117330 A117331
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KEYWORD
| nonn
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AUTHOR
| Zak Seidov (zakseidov(AT)yahoo.com), Mar 08 2006
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