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A113913 Number of distinct prime factors of 3^(3^n)+1. 1
1, 2, 4, 6, 11, 20, 27 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The term omega(3^(3^6)+1) was obtained with ECM factoring.
LINKS
FORMULA
a(n) = A001221(A129290(n)).
MATHEMATICA
Table[PrimeNu[3^(3^n) + 1], {n, 1, 10}] (* G. C. Greubel, May 16 2017 *)
PROG
(PARI) for(x=1, 6, print1( omega(3^(3^x)+1), ", "))
CROSSREFS
Sequence in context: A000694 A164137 A018170 * A002097 A026757 A026385
KEYWORD
hard,more,nonn
AUTHOR
Jorge Coveiro, Jan 29 2006
STATUS
approved

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Last modified May 23 16:36 EDT 2024. Contains 372765 sequences. (Running on oeis4.)