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A098765 a(n) = least k such that (k*P(n)#)^2 + 1 ((k+1)*P(n)#)^2 + 1 and ((k+2)*P(n)#)^2 + 1 are 3 primes with P(i) = i-th prime, P(i)# = i-th primorial. 0
1, 34, 3, 252, 16, 104, 246, 562, 895, 459, 3656, 165, 409, 869, 3075, 1568, 1310, 7723, 4035, 21114, 10634, 2185, 143, 11861, 24850, 3168, 4750, 14373, 565, 22576, 7971, 2063, 17528, 58449 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

(3*2*3*5)^2+1=8101 prime

(4*2*3*5)^2+1=14401 prime

(5*2*3*5)^2+1=22501 prime

so a(3)=3

CROSSREFS

Sequence in context: A022070 A123301 A037933 * A071788 A220133 A118497

Adjacent sequences:  A098762 A098763 A098764 * A098766 A098767 A098768

KEYWORD

nonn

AUTHOR

Pierre CAMI, Oct 02 2004

STATUS

approved

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Last modified May 23 15:18 EDT 2013. Contains 225610 sequences.