A345952 - OEIS

%I #11 Jul 04 2021 17:45:41

%S 0,0,0,1,0,0,0,1,1,0,0,1,0,0,0,1,0,1,0,0,0,0,0,1,1,0,1,0,0,0,0,1,0,0,

%T 0,1,0,0,0,1,0,0,0,0,1,0,0,1,1,1,0,0,0,1,0,1,0,0,0,0,0,0,1,1,0,0,0,0,

%U 0,0,0,1,0,0,1,0,0,0,0,1,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,1

%N a(n) = 1 if the largest prime power divisor of n (A034699) is greater than the largest prime divisor of n (A006530).

%H Antti Karttunen, <a href="/A345952/b345952.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%F a(n) = 1 if A034699(n) > A006530(n), 0 otherwise.

%F a(n) >= A268340(n), for all n >= 1.

%F a(n) >= A345951(n), for all n >= 1.

%o (PARI) A345952(n) = { my(f=factor(n), k=#f[, 1]); for(i=1, k, if(f[i, 1]^f[i, 2]>f[k, 1], return(1))); (0); }; \\ After program given in A122145.

%Y Characteristic function of A122145.

%Y Cf. A006530, A034699, A268340, A345951.

%K nonn

%O 1

%A _Antti Karttunen_, Jul 04 2021