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A350576 a(n) = n/A055874(n) - A055874(n).

%I A350576 #14 Jan 09 2022 09:58:23
%S A350576 0,-1,2,0,4,-1,6,2,8,3,10,-1,12,5,14,6,16,3,18,8,20,9,22,2,24,11,26,
%T A350576 12,28,7,30,14,32,15,34,5,36,17,38,18,40,11,42,20,44,21,46,8,48,23,50,
%U A350576 24,52,15,54,26,56,27,58,4,60,29,62,30,64,19,66,32,68,33,70,14,72,35,74
%N A350576 a(n) = n/A055874(n) - A055874(n).
%H A350576 Michel Marcus, <a href="/A350576/b350576.txt">Table of n, a(n) for n = 1..10000</a>
%F A350576 a(n) = A350509(n) - A055874(n).
%F A350576 a(n) = n-1 if n is odd.
%t A350576 a[n_] := Module[{k = 1}, While[Divisible[n, k], k++]; k--; n/k - k]; Array[a, 100] (* _Amiram Eldar_, Jan 07 2022 *)
%o A350576 (PARI) a4(n) = my(m=1); while ((n % m) == 0, m++); m - 1; \\ A055874
%o A350576 a(n) = my(x=a4(n)); n/x - x;
%o A350576 (Python)
%o A350576 def a(n):
%o A350576     m = 2
%o A350576     while n%m == 0: m += 1
%o A350576     return n//(m-1) - (m-1)
%o A350576 print([a(n) for n in range(1, 76)]) # _Michael S. Branicky_, Jan 07 2022
%Y A350576 Cf. A055874, A350509.
%Y A350576 Cf. A005408 (odd numbers), A056737 (another difference n/d-d).
%K A350576 sign
%O A350576 1,3
%A A350576 _Michel Marcus_, Jan 07 2022, after a suggestion from _Charles Kusniec_