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%I #12 Oct 07 2017 10:10:33
%S 0,0,0,1,-1,1,-1,1,0,0,-1,1,-1,1,0,1,-2,1,-1,1,0,0,-1,2,-1,0,0,0,-1,1,
%T -1,1,0,0,0,1,-2,1,0,1,-2,1,-1,1,0,0,-1,1,0,0,0,0,-1,2,-1,1,-1,0,-1,2,
%U -2,1,0,1,-1,0,-1,1,0,0,-1,1,-1,1,0,0,0,0,-1,1,1,-1,-1,2,-1,0,0,1,-2,2,-1,0,0,0,0,1,-2,1,0,1,-2
%N a(n) = f(f(n+1)) - f(f(n)), where f(0) = 0 and f(m) = bigomega(m) = A001222(m) for m > 0.
%H Antti Karttunen, <a href="/A111405/b111405.txt">Table of n, a(n) for n = 0..20000</a>
%o (PARI)
%o f(n) = if(n==0,0,bigomega(n));
%o A111405(n) = f(f(n+1)) - f(f(n)); \\ _Antti Karttunen_, Oct 07 2017
%Y Cf. A001222, A111407.
%K sign
%O 0,17
%A _N. J. A. Sloane_, Nov 12 2005
%E Description clarified by _Antti Karttunen_, Oct 07 2017