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A141219 Nonprimes of the form ((p(max)+1)*..*p*(p(min)-1)), where a(0)=1 and (p(max))*..*p*(p(min)=k(n)=n-th nonprime. 3
1, 4, 6, 8, 6, 8, 8, 12, 12, 12, 12, 16, 12, 16, 24, 14, 24, 16, 18, 24, 24, 18, 32, 24, 20, 28, 24, 24, 24, 36, 24, 32, 48, 30, 36, 28, 36, 48, 32, 40, 30, 36, 32, 48, 48, 56, 36, 36, 48, 40, 48, 38, 60, 40, 72, 42, 48, 72, 42, 48, 72, 44, 60, 48, 54, 84, 48, 64, 48, 80, 64, 56 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

If k(1)=4=(p(max)=2)*(p(min)=2), then (2+1)*(2-1)=3*1=3

(prime).

If k(2)=6=(p(max)=3)*(p(min)=2), then

(3+1)*(2-1)=4*1=4 (nonprime)=a(1).

If k(3)=8=(p(max)=2)*(p=2)*(p(min)=2), then

(2+1)*2*(2-1)=3*2*1=6 (nonprime)=a(2), etc.

CROSSREFS

Sequence in context: A083257 A201336 A188930 * A159576 A199626 A163639

Adjacent sequences:  A141216 A141217 A141218 * A141220 A141221 A141222

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov (2stepan(AT)rambler.ru) Aug 7 2008

EXTENSIONS

a(6), a(54), a(71) corrected by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 18 2008

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.