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A145174 Least a(n) such that p(n)#*(p(n)#-a(n))-1 and p(n)#*(p(n)#-a(n))+1 are twin primes with p(i)#=i-th primorial 1
0, 1, 3, 1, 5, 4, 44, 13, 31, 173, 25, 19, 75, 99, 47, 77, 166, 468, 43, 1, 344, 7, 44, 398, 434, 901, 246, 246, 91, 755, 1066, 839, 1605, 560, 460, 1649, 426, 1203, 732, 1055, 130, 1821, 1645, 360, 4779, 2414, 272, 668, 2410, 3957, 2514, 685, 3484, 3139, 5680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Pierre CAMI, Table of n, a(n) for n = 1..200

EXAMPLE

2*3*(2*3-1)-1=29 prime as 31 so a(2)=1

CROSSREFS

Cf. A144946, A144947, A145173

Sequence in context: A007085 A094648 A096975 * A228785 A135184 A210224

Adjacent sequences:  A145171 A145172 A145173 * A145175 A145176 A145177

KEYWORD

nonn

AUTHOR

Pierre CAMI, Oct 03 2008

EXTENSIONS

Corrected and extended by Ray Chandler, Jan 12 2009

STATUS

approved

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Last modified August 19 01:29 EDT 2017. Contains 290787 sequences.