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%I #17 Apr 30 2021 06:05:55
%S 0,0,1,0,1,0,2,1,1,0,0,0,1,0,1,1,0,0,2,0,0,0,1,1,1,0,0,0,0,0,0,0,1,0,
%T 0,1,0,0,0,-1,-1,0,0,0,1,0,1,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,-1,
%U 0,0,0,0,0,1,0,1,0,-1,0,0,1,0,0,-1,0,0,0,0,1,1,1,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
%H Antti Karttunen, <a href="/A286106/b286106.txt">Table of n, a(n) for n = 1..10000</a>
%F a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
%o (Scheme) (define (A286106 n) (if (= 1 n) 0 (- (A286105 (A285735 n)) (A286105 (A285734 n)))))
%o (Python)
%o from sympy.ntheory.factor_ import core
%o def issquarefree(n): return core(n) == n
%o def a285734(n):
%o if n==1: return 0
%o j=n//2
%o while True:
%o if issquarefree(j) and issquarefree(n - j): return j
%o else: j-=1
%o def a285735(n): return n - a285734(n)
%o def a286105(n): return 0 if n==1 else 1 + max(a286105(a285734(n)), a286105(a285735(n)))
%o def a286106(n): return 0 if n==1 else a286105(a285735(n)) - a286105(a285734(n))
%o print([a286106(n) for n in range(1, 121)]) # _Indranil Ghosh_, May 02 2017
%Y Cf. A285734, A285735, A286105, A286107.
%K sign
%O 1,7
%A _Antti Karttunen_, May 02 2017
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