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 A275383 Number of prime factors (with multiplicity) of generalized Fermat number 12^(2^n) + 1. 3
 1, 2, 2, 3, 2, 2, 5, 2, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Arkadiusz Wesolowski, A 96-digit prime factor of b(8) FORMULA a(n) = A001222(A152585(n)). - Felix FrÃ¶hlich, Jul 25 2016 EXAMPLE b(n) = 12^(2^n) + 1. Complete Factorizations b(0) = 13 b(1) = 5*29 b(2) = 89*233 b(3) = 17*97*260753 b(4) = 153953*1200913648289 b(5) = 769*44450180997616192602560262634753 b(6) = 36097*81281*69619841*73389730593973249*P35 b(7) = 257*P136 b(8) = 8253953*295278642689*5763919006323142831065059613697*P96*P132 MATHEMATICA Table[PrimeOmega[12^(2^n) + 1], {n, 0, 7}] (* Michael De Vlieger, Jul 26 2016 *) PROG (PARI) a(n) = bigomega(factor(12^(2^n)+1)) CROSSREFS Cf. A152585, A273950. Sequence in context: A068050 A210967 A343534 * A206762 A212281 A225637 Adjacent sequences:  A275380 A275381 A275382 * A275384 A275385 A275386 KEYWORD nonn,hard,more AUTHOR Arkadiusz Wesolowski, Jul 25 2016 EXTENSIONS a(8) was found in 2009 by Tom Womack STATUS approved

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Last modified July 27 18:27 EDT 2021. Contains 346308 sequences. (Running on oeis4.)