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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
OFFSET
0,2
FORMULA
a(n) = A001222(A152585(n)). - Felix Fröhlich, 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
Sequence in context: A068050 A210967 A343534 * A351627 A206762 A212281
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(8) was found in 2009 by Tom Womack
STATUS
approved