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A375535 a(n) = n - A075860(n).

%I A375535 #8 Aug 28 2024 11:26:05
%S A375535 1,0,0,2,0,1,0,6,6,3,0,7,0,11,13,14,0,13,0,13,14,9,0,19,20,24,24,25,0,
%T A375535 23,0,30,30,15,30,31,0,31,37,33,0,37,0,31,43,41,0,43,42,43,44,50,0,49,
%U A375535 53,53,44,27,0,53,0,59,56,62,60,64,0,49,67,67,0,67,0,72,73,69,72,73
%N A375535 a(n) = n - A075860(n).
%C A375535 If p is a prime number, then a(p)=0.
%e A375535 For n=15, a(15) = 15-2 = 13.
%p A375535 f := proc(n)
%p A375535     option remember:
%p A375535     if isprime(n) then
%p A375535         n
%p A375535     else
%p A375535         procname(convert(numtheory:-factorset(n), `+`))
%p A375535     end if
%p A375535 end proc:
%p A375535 f(1) := 0:
%p A375535 seq(n - f(n), n = 1..100);
%o A375535 (Python)
%o A375535 from sympy import primefactors
%o A375535 def a(n, pn):
%o A375535     if n == pn:
%o A375535         return n
%o A375535     else:
%o A375535         return a(sum(primefactors(n)), n)
%o A375535 print([i-a(i, None) for i in range(1, 100)])
%Y A375535 Cf. A075860.
%K A375535 nonn
%O A375535 1,4
%A A375535 _Rafik Khalfi_, Aug 18 2024