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A103356 Least k such that k*((p(n)#)^2)-1 is prime with p(i)#=i-th primorial. 0
1, 2, 3, 3, 6, 17, 13, 13, 5, 6, 2, 11, 14, 15, 3, 7, 77, 6, 20, 53, 52, 6, 13, 8, 41, 52, 24, 26, 31, 41, 5, 31, 21, 28, 43, 57, 11, 18, 47, 19, 8, 33, 24, 30, 43, 10, 17, 213, 29, 15, 45, 60, 50, 26, 48, 18, 18, 78, 8, 59, 13, 33, 145, 23, 154, 79, 65, 21, 18, 23, 30, 19, 159, 46, 45 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

1*2^2-1=3 prime so a(1)=1

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

2*((2*3)^2)-1=71 prime so a(2)=2

1*((2*3*5)^2)-1=899 composite

2*((2*3*5)^2)-1=1799 composite

3*((2*3*5)^2)-1=2699 prime so a(3)=3

CROSSREFS

Sequence in context: A180887 A173094 A087989 * A028257 A100228 A111003

Adjacent sequences:  A103353 A103354 A103355 * A103357 A103358 A103359

KEYWORD

nonn

AUTHOR

Pierre CAMI (pierre-cami(AT)bbox.fr), Mar 20 2005

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Last modified February 16 16:00 EST 2012. Contains 205938 sequences.