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A143181 Sequence of a(n) such that : define p(0)=2 the first prime, then p(n+1)=least prime p of the form a(n)*p(n)*(a(n)*p(n)+1)-1 with a twin prime p+2. 1
1, 1, 7, 135, 549, 7209, 1741, 4197, 172434, 2638147 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
EXAMPLE
1*2*(1*2+1)-1=5, 7 twin prime so a(1)=1
1*5*(1*5+1)-1=29, 31 twin prime so a(2)=1
CROSSREFS
Cf. A120393.
Sequence in context: A119670 A003374 A001533 * A183478 A292395 A081793
KEYWORD
more,nonn
AUTHOR
Pierre CAMI, Jul 28 2008
STATUS
approved

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Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)