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0,4
Ray Chandler, Table of n, a(n) for n = 0..310 (from Kamada link)
Makoto Kamada, Factorizations of 100...001.
a(n) = A104223(n-1), n>0. - R. J. Mathar, Aug 08 2008
a(n) = A001221(A062397(n)). - Ray Chandler, May 02 2017
a(11) = 4 because 10^11+1 = 11*11*23*4093*8779: 4 distinct factors.
Table[Length[FactorInteger[10^n + 1]], {n, 0, 50}] (* Stefan Steinerberger, Jun 13 2006 *)
Cf. A001221, A003021, A038371, A057934, A062397, A104223.
Sequence in context: A178250 A174550 A058758 * A104223 A057934 A122396
Adjacent sequences: A119701 A119702 A119703 * A119705 A119706 A119707
nonn
Lekraj Beedassy, Jun 09 2006
More terms from Don Reble, Jun 13 2006
approved