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A104038 Least k such that k*(k+1)*Mersenne-prime(n)+1 is prime. 0
1, 2, 3, 12, 8, 3, 5, 14, 17, 69, 189, 42, 392, 377, 12, 2007, 434, 744, 705, 1089, 1109, 7833 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

1*2*(2^2-1)+1=7 prime so k(1)=1

2*3*(2^3-1)+1=43 prime so k(2)=2

3*4*(2^5-1)+1=373 prime so k(3)=3

CROSSREFS

Sequence in context: A282075 A282514 A320810 * A112979 A225723 A092972

Adjacent sequences:  A104035 A104036 A104037 * A104039 A104040 A104041

KEYWORD

more,nonn

AUTHOR

Pierre CAMI, Mar 31 2005

STATUS

approved

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Last modified August 12 17:17 EDT 2020. Contains 336439 sequences. (Running on oeis4.)