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%I #11 May 07 2024 11:17:35
%S 1,2,3,4,4,5,4,6,5,6,5,9,5,6,12,8,4,10,5,11,7,6,7,12,8,13,8,10,6,14,8,
%T 12,9,10,18,18,6,11,11,19,8,16,5,12,13,7,7,20,5,18,12,14,7,21,12,19,
%U 10,10,7,24,7,10,20,15,13,19,6,19,11,19,9,25,6,13
%N Number of distinct prime factors of n^n-n.
%F a(n) = A001221(A061190(n)).
%t a[n_] := a[n] = PrimeNu[n^n - n];
%t Table[a[n], {n, 2, 75}] (* _Robert P. P. McKone_, May 07 2024 *)
%o (PARI) a(n) = omega(n^n-n);
%o (Python)
%o from sympy.ntheory.factor_ import primenu
%o def A372599(n): return primenu(n*(n**(n-1)-1)) # _Chai Wah Wu_, May 07 2024
%Y Cf. A001221, A061190, A372546, A372229, A344870, A344869.
%K nonn
%O 2,2
%A _Tyler Busby_, May 06 2024
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