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%I #9 Jan 18 2019 20:54:49
%S 1,1,0,1,1,0,1,1,0,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,0,0,0,1,1,0,1,1,1,0,
%T 0,0,1,0,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,0,1,1,0,1,0,1,0,1,1,0,0,1,1,
%U 1,1,1,0,1,0,1,1,0,0,1,1,0,0,1,0,0,0,1,1,1,0,0,1,1,0,0,1,1,1,1,0,1,0,1,1,1
%N a(n) = A079559(A156552(n)).
%C Characteristic function of numbers n whose unary-binary encoded factorization [A156552(n)] is a term of A005187.
%C Characteristic function of the range of f(n) = A005940(1+A005187(n)).
%H Antti Karttunen, <a href="/A323512/b323512.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) = A079559(A156552(n)).
%o (PARI)
%o A036987(n) = !bitand(n,1+n);
%o A053644(n) = { my(k=1); while(k<=n, k<<=1); (k>>1); }; \\ From A053644
%o A053645(n) = (n-A053644(n));
%o A079559(n) = if(!n,1,(1-A036987(1+n))*A079559(A053645(1+n)));
%o A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
%o A323512(n) = A079559(A156552(n));
%Y Cf. A005187, A005940, A079559, A156552.
%Y Cf. also A323511.
%K nonn
%O 1
%A _Antti Karttunen_, Jan 18 2019
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