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A083685 a(n) is the smallest prime of the form k*lcm(1..n) - 1. 0
2, 3, 5, 11, 59, 59, 419, 839, 5039, 5039, 55439, 55439, 1081079, 1081079, 1081079, 1441439, 24504479, 24504479, 232792559, 232792559, 232792559, 232792559, 5354228879, 5354228879, 53542288799, 53542288799, 1044074631599 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..27.

EXAMPLE

a(9) = 5039: lcm(1..9) = 2520; 2519 is not a prime but 2*2520 - 1 = 5039 is a prime.

PROG

(PARI) a(n) = {my(lcmn = lcm(vector(n, k, k)), k = 1); while(!isprime(p = k*lcmn-1), k++); p; } \\ Michel Marcus, Mar 15 2018

CROSSREFS

Cf. A070858.

Sequence in context: A000905 A065296 A114895 * A243755 A242334 A087524

Adjacent sequences:  A083682 A083683 A083684 * A083686 A083687 A083688

KEYWORD

nonn

AUTHOR

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 15 2003

EXTENSIONS

Corrected and extended by Vladeta Jovovic, Jun 16 2003

STATUS

approved

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Last modified September 27 11:15 EDT 2020. Contains 337380 sequences. (Running on oeis4.)