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A103557 Least k such that k*((p(n)#)^2)-1 and k*((p(n)#)^2)+1 are twin primes. 1
1, 2, 7, 6, 6, 104, 152, 116, 181, 6, 78, 89, 85, 262, 133, 57, 77, 35, 237, 140, 315, 397, 663, 48, 1135, 382, 318, 261, 542, 352, 120, 31, 1430, 553, 43, 913, 1235, 122, 1008, 602, 222, 1562, 255 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

1*((2*3)^2)-1=35 composite

2*((2*3)^2)-1=71 prime 2*((2*3)^2)+1=73 prime twin of 71 so a(2)=2

CROSSREFS

Sequence in context: A127817 A199173 A047232 * A210963 A210965 A189959

Adjacent sequences:  A103554 A103555 A103556 * A103558 A103559 A103560

KEYWORD

nonn

AUTHOR

Pierre CAMI, Mar 23 2005

STATUS

approved

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Last modified December 13 08:08 EST 2018. Contains 318082 sequences. (Running on oeis4.)