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A140209 Nonprimes of the form ((x+y)/3+2)/(x-y), where x=prime and y=nonprime. 0
1, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 65, 66, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 91, 92, 93, 94, 95, 96, 98, 99 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..71.

EXAMPLE

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

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

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

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

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

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

etc.

CROSSREFS

Cf. A000040, A002808, A018252, A141468.

Sequence in context: A018252 A141468 A140347 * A077091 A340268 A340058

Adjacent sequences:  A140206 A140207 A140208 * A140210 A140211 A140212

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Aug 28 2008

EXTENSIONS

Inserted 4 (x=101, y=85), 6 (x=149, y=133), 8 (x=347, y=319) etc. R. J. Mathar, Apr 14 2010

STATUS

approved

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Last modified March 4 08:38 EST 2021. Contains 341781 sequences. (Running on oeis4.)