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A286106
a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
6
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, 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, 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
OFFSET
1,7
LINKS
FORMULA
a(1) = 0, and for n > 1, a(n) = A286105(A285735(n)) - A286105(A285734(n)).
PROG
(Scheme) (define (A286106 n) (if (= 1 n) 0 (- (A286105 (A285735 n)) (A286105 (A285734 n)))))
(Python)
from sympy.ntheory.factor_ import core
def issquarefree(n): return core(n) == n
def a285734(n):
if n==1: return 0
j=n//2
while True:
if issquarefree(j) and issquarefree(n - j): return j
else: j-=1
def a285735(n): return n - a285734(n)
def a286105(n): return 0 if n==1 else 1 + max(a286105(a285734(n)), a286105(a285735(n)))
def a286106(n): return 0 if n==1 else a286105(a285735(n)) - a286105(a285734(n))
print([a286106(n) for n in range(1, 121)]) # Indranil Ghosh, May 02 2017
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, May 02 2017
STATUS
approved