A323154 - OEIS

%I #7 Jan 09 2019 21:21:52

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

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

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

%N a(n) = 1 if n divides A048146(n) = (sigma(n)-usigma(n)), 0 otherwise.

%C Characteristic function of A064594.

%C a(n) = 1 if and only if n divides A048146(n) = (A000203(n) - A034448(n)).

%C Differs from A008966 at n = 24, 112, 1984, 2520, 31320, 32512, ... (A064595).

%H Antti Karttunen, <a href="/A323154/b323154.txt">Table of n, a(n) for n = 1..65537</a>

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

%o (PARI)

%o A034448(n) = { my(f=factorint(n)); prod(k=1, #f~, 1+(f[k, 1]^f[k, 2])); }; \\ After code in A034448

%o A323154(n) = !((sigma(n)-A034448(n))%n);

%Y Cf. A000203, A008966, A034448, A048146, A064594, A064595.

%K nonn

%O 1

%A _Antti Karttunen_, Jan 09 2019