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a(n) = 1 if A353749(n) > A353749(sigma(n)), otherwise 0. Here A353749(n) = phi(n)*A064989(n), and A064989 shifts the prime factorization one step towards lower primes.
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%I #9 May 12 2022 16:13:05

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

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

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

%N a(n) = 1 if A353749(n) > A353749(sigma(n)), otherwise 0. Here A353749(n) = phi(n)*A064989(n), and A064989 shifts the prime factorization one step towards lower primes.

%H Antti Karttunen, <a href="/A353760/b353760.txt">Table of n, a(n) for n = 1..65537</a>

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

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = 1 if A353757(n) is negative, otherwise 0.

%o (PARI)

%o A064989(n) = { my(f=factor(n>>valuation(n,2))); for(i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };

%o A353749(n) = (eulerphi(n)*A064989(n));

%o A353760(n) = { my(s=sigma(n)); (A353749(s)<A353749(n)); };

%Y Characteristic function of A353758.

%Y Cf. A353749, A353750, A353757, A353759.

%Y Cf. also A353681, A353638, A353639.

%K nonn

%O 1

%A _Antti Karttunen_, May 10 2022