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A117244 Single (or isolated or non-twin) primes (A007510) that are not Chen primes (A109611). 0
79, 97, 163, 173, 223, 277, 331, 367, 373, 383, 397, 439, 457, 547, 593, 607, 613, 673, 691, 709, 727, 733, 739, 757, 773, 853, 907, 929, 967, 997, 1013, 1069, 1087, 1103, 1123, 1129, 1171, 1181, 1213, 1223, 1237, 1249, 1307, 1373, 1423, 1433, 1447, 1493 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..47.

EXAMPLE

79 is single prime, but not Chen prime.

MAPLE

isA001358 := proc(n) numtheory[bigomega](n) = 2 ; end proc: isA109611 := proc(n) if isprime(n) then isprime(n+2) or isA001358(n+2) ; else false; end if; end proc: isA007510 := proc(n) if isprime(n) then not isprime(n-2) and not isprime(n+2) ; else false; end if ; end proc: isA117244 := proc(n) isA007510(n) and not isA109611(n) ; end proc: for n from 1 to 4000 do if isA117244(n) then printf("%d, ", n) ; fi; end do ; # R. J. Mathar, Dec 09 2009

CROSSREFS

Cf. A007510, A109611.

Sequence in context: A039544 A091819 A318158 * A039436 A043259 A044039

Adjacent sequences:  A117241 A117242 A117243 * A117245 A117246 A117247

KEYWORD

nonn

AUTHOR

Jani Melik, Apr 22 2006

EXTENSIONS

Terms beyond 397 from R. J. Mathar, Dec 09 2009

STATUS

approved

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Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)