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%I #29 Jul 27 2016 10:20:29
%S 0,1,1,2,1,1,1,5,4,6
%N Number of odd prime factors (with multiplicity) of generalized Fermat number 3^(2^n) + 1.
%H Arkadiusz Wesolowski, <a href="/A275377/a275377.txt">A 93-digit prime factor of b(9)</a>
%F a(n) = A001222(A059919(n)) - 1 for n > 0. - _Felix Fröhlich_, Jul 25 2016
%e b(n) = (3^(2^n) + 1)/2.
%e Complete Factorizations
%e b(0) = 2
%e b(1) = 5
%e b(2) = 41
%e b(3) = 17*193
%e b(4) = 21523361
%e b(5) = 926510094425921
%e b(6) = 1716841910146256242328924544641
%e b(7) = 257*275201*138424618868737*3913786281514524929*P21
%e b(8) = 12289*8972801*891206124520373602817*P90
%e b(9) = 134382593*22320686081*12079910333441*100512627347897906177*P93*P101
%o (PARI) a001222(n) = bigomega(n)
%o a059919(n) = 3^(2^n)+1
%o a(n) = if(n==0, 0, a001222(a059919(n))-1) \\ _Felix Fröhlich_, Jul 25 2016
%Y Cf. A059919, A273945.
%K nonn,hard,more
%O 0,4
%A _Arkadiusz Wesolowski_, Jul 25 2016
%E a(9) was found in 2008 by Tom Womack
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