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A171156
Numbers of the form 2p or 3p where p is a prime greater than 3.
2
10, 14, 15, 21, 22, 26, 33, 34, 38, 39, 46, 51, 57, 58, 62, 69, 74, 82, 86, 87, 93, 94, 106, 111, 118, 122, 123, 129, 134, 141, 142, 146, 158, 159, 166, 177, 178, 183, 194, 201, 202, 206, 213, 214, 218, 219, 226, 237, 249, 254, 262, 267, 274, 278, 291, 298, 302
OFFSET
1,1
COMMENTS
Squarefree semiprimes (A006881) which have exactly one prime factor <=3 [R. J. Mathar, Dec 09 2009]
MAPLE
isA171156 := proc(n) local f; f := numtheory[factorset](n) ; if numtheory[bigomega](n) = 2 and nops(f) = 2 then if f = {2, 3} then false; else (n mod 2) = 0 or (n mod 3) = 0 ; fi; else false; fi; end:
for n from 10 to 500 do if isA171156(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Dec 09 2009
CROSSREFS
KEYWORD
nonn,easy,less
AUTHOR
EXTENSIONS
Edited by Charles R Greathouse IV, Mar 25 2010
STATUS
approved