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A286106 a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)). 6

%I

%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=int(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 xrange(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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Last modified June 18 07:44 EDT 2019. Contains 324203 sequences. (Running on oeis4.)