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%I #6 Jan 07 2021 08:37:36
%S 1,1,1,1,1,0,1,1,1,0,0,0,1,0,1,1,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,1,1,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,1,1,0,0,0,
%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1
%N a(n) = 1 if n is of the form 2^i - 2^j with i >= j, and 0 otherwise.
%H Antti Karttunen, <a href="/A340375/b340375.txt">Table of n, a(n) for n = 0..65537</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(0) = 1; for n > 1, a(n) = A209229(1+A000265(n)).
%o (PARI)
%o A000265(n) = (n>>valuation(n,2));
%o A209229(n) = (n && !bitand(n,n-1));
%o A340375(n) = if(!n,1,A209229(1+A000265(n)));
%o (PARI) A340375(n) = if(n<5, 1, n>>=valuation(n, 2); n++; n>>valuation(n, 2)==1); \\ From standalone function "is" given in A023758
%Y Characteristic function of A023758.
%Y Cf. A000265, A209229.
%K nonn
%O 0
%A _Antti Karttunen_, Jan 06 2021
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