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%I #9 Jan 09 2019 21:21:42
%S 0,1,1,0,1,1,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,1,1,0,1,0,0,0,
%T 0,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,
%U 0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,0,0
%N a(n) = 1 if n is either a prime or a perfect number, 0 otherwise.
%C Characteristic function of A053813.
%C Differs from A323152 at positions n = 1, 120, 672, 30240, 32760, ...
%H Antti Karttunen, <a href="/A323153/b323153.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) A323153(n) = ((n>1)&&!(n%sumdiv(n,d,(d<n)*d)));
%Y Cf. A000040, A000396, A053813, A053814, A323152.
%K nonn
%O 1
%A _Antti Karttunen_, Jan 09 2019
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