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%I #13 May 09 2021 11:18:42
%S 1,2,3,2,5,3,7,2,3,5,11,4,13,7,5,2,17,9,19,5,7,11,23,4,5,13,3,7,29,10,
%T 31,2,11,17,7,9,37,19,13,5,41,7,43,11,5,23,47,4,7,5,17,13,53,9,11,8,
%U 19,29,59,10,61,31,9,2,13,33,67,17,23,35,71,9,73,37,5,19,11,13,79,5,3,41,83,28,17,43,29,11,89,10,13,23,31,47,19,32,97,49,11,5
%N a(n) = n / A285707(n).
%H Antti Karttunen, <a href="/A285708/b285708.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n / A285707(n).
%F For n > 1, a(n) = n / gcd(n, A079277(n)).
%o (Scheme) (define (A285708 n) (/ n (A285707 n)))
%o (Python)
%o from sympy import divisors, gcd
%o from sympy.ntheory.factor_ import core
%o def a007947(n): return max(i for i in divisors(n) if core(i) == i)
%o def a079277(n):
%o k=n - 1
%o while True:
%o if a007947(k*n) == a007947(n): return k
%o else: k-=1
%o def a285707(n): return 1 if n==1 else gcd(n, a079277(n))
%o print([n//a285707(n) for n in range(1, 151)]) # _Indranil Ghosh_, Apr 27 2017
%Y Cf. A079277, A285707.
%K nonn
%O 1,2
%A _Antti Karttunen_, Apr 26 2017
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