OFFSET
1,2
COMMENTS
Some terms above 10^15: 26435035805519327, 158975398896178078, 64044049390757098943, 1063423126446412987081943, 1091220919655042176978844783, 81074850280355100090334498663, 6317483763950169936179578094903, 5672799393875320397186007124651847, 170923900137537174138295268515194974, 195746953975871672436191077726091399305155458, 325665752547333314939363628501536024940097079718953, 953533053776414279913696071891872697927468471633033, 85791212788381063775490416118630897060666265030605503, 334519297382630382793758729321508383611586565722054114034741260213364710519401967713. - Max Alekseyev, Jun 18 2014
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..2617 (all terms below 10^15)
MATHEMATICA
Join[{1, 2}, Select[Range[107000000], PowerMod[4, #, #]==2&]] (* Harvey P. Dale, Jun 13 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jon E. Schoenfield, May 26 2007
EXTENSIONS
Terms a(28) onward from Max Alekseyev, Jun 18 2014
b-file corrected by Max Alekseyev, Oct 09 2016
STATUS
approved