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A140209 Nonprimes of the form ((x+y)/3+2)/(x-y), where x=prime and y=nonprime. 0


%S 1,4,6,8,9,10,12,14,15,16,18,20,21,22,24,25,26,27,28,30,32,33,34,35,

%T 36,38,39,40,42,44,45,46,48,49,50,51,52,54,55,56,57,58,60,62,63,65,66,

%U 69,70,72,74,75,76,77,78,80,81,82,84,85,86,87,88,91,92,93,94,95,96,98,99

%N Nonprimes of the form ((x+y)/3+2)/(x-y), where x=prime and y=nonprime.

%C x=p(i)=i-th prime and y=n(j)=j-th nonprime.

%e If x=5 and y=1, then ((5+1)/3+2)/(5-1)=4/4=1=a(1).

%e If x=53 and y=49, then ((53+49)/3+2)/(53-49)=36/4=9=a(2).

%e If x=59 and y=55, then ((59+55)/3+2)/(59-55)=40/4=10=a(3).

%e If x=89 and y=85, then ((89+85)/3+2)/(89-85)=90/4=15=a(4).

%e If x=149 and y=145, then ((149+145)/3+2)/(149-145)=100/4=25=a(5).

%e If x=179 and y=174, then ((179+174)/3+2)/(179-174)=120/4=30=a(6),

%e etc.

%Y Cf. A000040, A002808, A018252, A141468.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Aug 28 2008

%E Inserted 4 (x=101, y=85), 6 (x=149, y=133), 8 (x=347, y=319) etc. _R. J. Mathar_, Apr 14 2010

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Last modified October 15 21:38 EDT 2021. Contains 348034 sequences. (Running on oeis4.)