Problems & Puzzles: Puzzles

Problem 78.  a(10) in A177892

G.L. Honaker Jr., sent the following curio & puzzle:

Regarding A177892, we know the solution for the first twelve terms, from a(0) to a(11), except for a(10).

a(10) is the number of distinct prime factors of:
in the Lucas-Lehmer sequence.

Q. Would you like to give a try factoring a(10) this December? 


On Dec 27, 2020, G. L. Honaker made me notice that:

22427452848394140276947044397991663611794141183 (47 digits) is the second known prime factor of a(10), and was found by someone named "Mathar". Obviously the first prime factor is 2.

Accordingly, the search is going on, even if the end is still far away...



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