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%I #11 Mar 29 2015 18:37:14
%S 1,1,1,1,1,2,1,1,1,2,1,2,2,2,2,1,1,2,1,2,2,2,1,2,1,3,1,2,2,3,1,1,2,2,
%T 2,2,2,2,3,2,2,3,2,2,2,2,2,2,1,2,2,3,1,2,2,2,2,3,1,3,2,2,2,1,3,3,1,2,
%U 2,3,2,2,2,3,2,2,2,4,2,2,1,3,1,3,2,3,3,2,2,3,3,2,2,3,2,2,1,2,2,2,3,3,1,3,3
%N a(1) = 1; for m >= 2, a(m) = sum{p|m} a(pi(p)), where the sum is over the distinct prime divisors p of m and pi(p) is the order of p among the primes = the number of primes <= p.
%t PrimeFactors[n_Integer] := Flatten[ Table[ # [[1]], {1}] & /@ FactorInteger[n]]; a[1] = 1; a[n_] := a[n] = (Plus @@ (a[ # ] & /@ PrimePi[ PrimeFactors[n]])); Table[ a[n], {n, 105}] (* _Robert G. Wilson v_, May 04 2004 *)
%Y Cf. A093321, A066328, A094162 (for where n first appears).
%K nonn,easy
%O 1,6
%A _Leroy Quet_, Apr 26 2004
%E More terms from _Robert G. Wilson v_, May 04 2004
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