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A101221 Least k such that (10^k)*(P(n)#) - 1 is prime with P(i)= i-th prime and P(i)#= ith-primorial. 0
1, 0, 0, 1, 0, 0, 3, 2, 1, 1, 40, 1, 0, 10, 10, 10, 7, 17, 4, 11, 15, 10, 11, 0, 24, 8, 11, 2, 18, 2, 6, 4, 58, 3, 14, 15, 1, 3, 13, 16, 1, 37, 4, 4, 8, 11, 80, 2, 37, 58, 55, 34, 15, 59, 26, 1, 32, 42, 47, 56, 47, 4, 57, 62, 27, 0, 14, 0, 12, 47, 19, 16, 39, 9, 71, 13, 6, 6, 25, 10, 1, 1 (list; graph; refs; listen; history; internal format)
OFFSET

1,7

EXAMPLE

(10^1)*2 -1 = 19 prime so k(1)=1

CROSSREFS

Sequence in context: A204124 A101479 A136170 * A137241 A016457 A181715

Adjacent sequences:  A101218 A101219 A101220 * A101222 A101223 A101224

KEYWORD

nonn

AUTHOR

Piere CAMI (pierre-cami(AT)bbox.fr), Dec 15 2004

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Last modified February 14 15:24 EST 2012. Contains 205626 sequences.