A122691 a(n) is the least prime factor of (9 * 10^(6*n-4) - 11) / 7.

127, 401, 19, 53, 151, 7, 139, 127, 19, 78721, 3458771, 19, 7, 38954263, 19, 79, 53, 19, 157, 7, 19, 127, 18191, 19, 12119, 421, 7, 107434435760557861791327959267859939351202240879711219728393537522815146155523913, 79, 19, 23196834569628410341642097660316821

Offset: 1

Author

Zak Seidov, Sep 22 2006

Keywords

• nonn

Examples

			n=2, (9*10^8-11)/7 = 128571427 = 401 * 320627 hence a(2)=401.
		

Links

• Sean A. Irvine, Table of n, a(n) for n = 1..69

Crossrefs

Cf. A100275, A122862.

Extensions

a(28) onward corrected by Sean A. Irvine, May 25 2024