1,1

Dario Alejandro Alpern, Factors of 1000 numbers up to googolplex.

(* For any individual n *) k = 17; While[ !PrimeQ[k] || PowerMod[10, 10^100, k] - n != 0, k += 2]; k

Cf. A072288.

Sequence in context: A067409 A007410 A072160 this_sequence A129911 A104808 A061686

Adjacent sequences: A078811 A078812 A078813 this_sequence A078815 A078816 A078817

hard,nonn,more

Ed Pegg, Jr. (edp(AT)wolfram.com) and Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 06 2002

Seventh term is not known. Sequence continues ?, 625392489737, 19, 37, 5419, 107, 23, 60149, 1733, 89, 8543, 17, 5261, 229, 8656871, 4273, 14009, 29, 509, 43628661784403, 24539783, 19, 347, 12414692011, 523, 151, 421, 35816135619181, 17, 23, 184309, ?, 181, 288481, 163, 41, 743, 13337, 71, 53, 19, 59, 113, 37957721, ... where the unknown numbers exceed 25 x 10^12. - Dario Alejandro Alpern (alpertron(AT)hotmail.com), Jul 03 2003