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A136151
Composites n with exactly two distinct prime divisors and of the form n=1+(any prime).
5
6, 12, 14, 18, 20, 24, 38, 44, 48, 54, 62, 68, 72, 74, 80, 98, 104, 108, 152, 158, 164, 192, 194, 200, 212, 224, 242, 272, 278, 284, 314, 332, 338, 368, 384, 398, 422, 432, 458, 464, 488, 500, 524, 542, 548, 578, 608, 614, 632, 648, 662, 674, 692, 734, 752, 758
OFFSET
1,1
LINKS
FORMULA
A008864 INTERSECT A007774. - R. J. Mathar, Feb 01 2008
MAPLE
isA136151 := proc(n) if isprime(n-1) then if nops(numtheory[factorset](n)) =2 then true; else false ; fi ; else false ; fi ; end: for i from 1 to 200 do n := ithprime(i)+1 ; if isA136151( n) then printf("%d, ", n) ; fi ; od: # R. J. Mathar, Feb 01 2008
MATHEMATICA
Select[Range[800], PrimeNu[#]==2&&PrimeQ[#-1]&] (* Harvey P. Dale, Jun 22 2018 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Dec 16 2007
EXTENSIONS
Edited by R. J. Mathar, Feb 01 2008
STATUS
approved