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A074054 Numbers n such that sum of composites from smallest prime factor of n to largest prime factor of n is prime. 1
22, 33, 44, 66, 88, 99, 106, 110, 132, 134, 154, 155, 159, 165, 176, 178, 198, 201, 202, 206, 212, 220, 231, 242, 264, 267, 268, 297, 303, 308, 309, 318, 330, 334, 352, 356, 363, 371, 396, 402, 404, 412, 413, 424, 440, 445, 462, 469, 477, 484, 493, 495, 501 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
22=2*11 and sum of composites between 2 and 11 is: 4+6+8+9+10 = 37, prime.
MATHEMATICA
scpQ[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]], a, b}, a = First[f]+ 1; b=Last[f]-1; PrimeQ[Total[Select[Range[a, b], !PrimeQ[#]&]]]]; Select[ Range[ 510], scpQ] (* Harvey P. Dale, May 07 2013 *)
CROSSREFS
Sequence in context: A190588 A072041 A067035 * A067287 A026044 A120146
KEYWORD
nonn
AUTHOR
Jason Earls, Sep 15 2002
STATUS
approved

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Last modified April 14 03:49 EDT 2024. Contains 371653 sequences. (Running on oeis4.)