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Records in A055460 (number of primes dividing the squarefree part of n!).
3

%I #8 Apr 17 2022 21:48:30

%S 0,1,2,3,4,5,6,7,9,10,11,12,14,15,16,17,18,19,20,22,23,24,25,26,27,28,

%T 30,31,32,34,36,37,38,39,41,42,43,44,46,47,49,50,51,52,53,54,55,57,58,

%U 59,60,61,63,64,65,67,68,69,70,72,74,75,76,77,78,79,80,81,82,85,86,87,88,91,93,95,98,99,100

%N Records in A055460 (number of primes dividing the squarefree part of n!).

%H Max Alekseyev, <a href="/A249017/b249017.txt">Table of n, a(n) for n = 1..100000</a>

%o (PARI) np=vector(10^6); b=-1; r=0; for(n=1,10^6, f=factor(n); for(i=1,matsize(f)[1], if(f[i,2]%2, r += (-1)^np[f[i,1]]; np[f[i,1]]=1-np[f[i,1]]; )); if(r>b,b=r;print1(b,", ")) )

%Y Cf. A055460, A055204, A249016 (indices of records).

%K nonn

%O 1,3

%A _Max Alekseyev_, Oct 19 2014