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A088388 Exponent of the largest prime power factor of n, a(1)=0.

%I A088388 #17 Apr 18 2023 08:29:50
%S A088388 0,1,1,2,1,1,1,3,2,1,1,2,1,1,1,4,1,2,1,1,1,1,1,3,2,1,3,1,1,1,1,5,1,1,
%T A088388 1,2,1,1,1,3,1,1,1,1,2,1,1,4,2,2,1,1,1,3,1,3,1,1,1,1,1,1,2,6,1,1,1,1,
%U A088388 1,1,1,2,1,1,2,1,1,1,1,4,4,1,1,1,1,1,1,1,1,2,1,1,1,1,1,5,1,2,1,2,1,1
%N A088388 Exponent of the largest prime power factor of n, a(1)=0.
%H A088388 Antti Karttunen, <a href="/A088388/b088388.txt">Table of n, a(n) for n = 1..65537</a>
%F A088388 A034699(n) = A088387(n)^a(n).
%t A088388 a[n_] := If[n==1, 0, MaximalBy[FactorInteger[n], #[[1]]^#[[2]]&][[1, 2]]];
%t A088388 Array[a, 100] (* _Jean-François Alcover_, Dec 03 2021 *)
%o A088388 (PARI) A088388(n) = if(1==n,0,my(f=factor(n)); isprimepower(vecmax(vector(#f[, 1], i, f[i, 1]^f[i, 2])))); \\ _Antti Karttunen_, Jul 22 2018
%o A088388 (Python)
%o A088388 from sympy import factorint
%o A088388 def A088388(n): return max(((p**e,e) for p, e in factorint(n).items()), default=(0,0))[1] # _Chai Wah Wu_, Apr 17 2023
%Y A088388 Cf. A034699, A088387.
%K A088388 nonn
%O A088388 1,4
%A A088388 _Reinhard Zumkeller_, Sep 28 2003