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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

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=int(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 xrange(1, 121)] # Indranil Ghosh, May 02 2017

CROSSREFS

Cf. A285734, A285735, A286105, A286107.

Sequence in context: A086013 A167687 A064692 * A079677 A286564 A316359

Adjacent sequences:  A286103 A286104 A286105 * A286107 A286108 A286109

KEYWORD

sign

AUTHOR

Antti Karttunen, May 02 2017

STATUS

approved

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Last modified May 25 11:04 EDT 2019. Contains 323539 sequences. (Running on oeis4.)