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 A275379 Number of prime factors (with multiplicity) of generalized Fermat number 6^(2^n) + 1. 3
 1, 1, 1, 2, 3, 3, 3, 7, 3, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS FORMULA a(n) = A001222(A078303(n)). - Felix Fröhlich, Jul 25 2016 EXAMPLE b(n) = 6^(2^n) + 1. Complete Factorizations b(0) = 7 b(1) = 37 b(2) = 1297 b(3) = 17*98801 b(4) = 353*1697*4709377 b(5) = 2753*145601*19854979505843329 b(6) = 4926056449*447183309836853377*28753787197056661026689 b(7) = 257*763649*50307329*3191106049*2339340566463317436161*        2983028405608735541756929*18247770097021321924017185281 b(8) = 18433*        69615986569139423375849495295909549956813828853888948633601*P137 b(9) = 80897*3360769*12581314681802812884728041373153281*        3513902440204553274892072241244613302018049*P311 MATHEMATICA Table[PrimeOmega[6^(2^n) + 1], {n, 0, 6}] (* Michael De Vlieger, Jul 26 2016 *) PROG (PARI) a(n) = bigomega(factor(6^(2^n)+1)) CROSSREFS Cf. A078303, A273947. Sequence in context: A170895 A141479 A055081 * A109833 A132005 A088041 Adjacent sequences:  A275376 A275377 A275378 * A275380 A275381 A275382 KEYWORD nonn,hard,more AUTHOR Arkadiusz Wesolowski, Jul 25 2016 EXTENSIONS a(8) was found in 2001 by Robert Silverman a(9) was found in 2007 by Nestor de Araújo Melo STATUS approved

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Last modified May 17 20:44 EDT 2021. Contains 343990 sequences. (Running on oeis4.)