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 A094474 a(n) is the largest prime factor of 2^n+3^n. 5
 5, 13, 7, 97, 11, 61, 463, 401, 577, 4621, 35839, 5521, 4057, 369181, 241, 14177, 7039, 181, 555029, 3121, 92233, 2414250301, 13249, 41432641, 513101, 13761229, 377604937, 3001769, 148466603, 24001, 22674269, 1607133116929, 22270249 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE n=100, 2^100+3^100=41.97.281.3121.742801.20017001.9937984196743741414107401 so a[100]=9937984196743741414107401. MATHEMATICA Table[Part[Reverse[Flatten[FactorInteger[2^w + 3^w]]], 2], {w, 1, 100}] CROSSREFS Sequence in context: A068530 A088315 A138296 * A064109 A175484 A210694 Adjacent sequences:  A094471 A094472 A094473 * A094475 A094476 A094477 KEYWORD nonn AUTHOR Labos Elemer, Jun 01 2004 STATUS approved

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Last modified August 20 18:56 EDT 2019. Contains 326154 sequences. (Running on oeis4.)