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a(n)=0 if n is in A055938, a(n)=1 if n is in A179016, otherwise (i.e., n is in A213717), a(n)=2.
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%I #18 Jul 17 2017 01:03:21

%S 1,1,0,1,1,0,0,1,1,0,2,1,0,0,0,1,1,0,2,1,0,0,2,1,0,2,1,0,0,0,0,1,1,0,

%T 2,1,0,0,2,1,0,2,1,0,0,0,1,2,0,1,2,0,0,1,2,0,2,1,0,0,0,0,0,1,1,0,2,1,

%U 0,0,2,1,0,2,1,0,0,0,1,2,0,1,2,0,0,1,2

%N a(n)=0 if n is in A055938, a(n)=1 if n is in A179016, otherwise (i.e., n is in A213717), a(n)=2.

%C Those natural numbers n for which a(n)=1 belong to the infinite trunk of "Carl White's beanstalk" (see A179016), while the numbers n for which a(n)=0, are the leaves (terminal, dead-end nodes) of the same beanstalk, while those n for which a(n)=2, are non-terminal nodes in its finite tendrils.

%H Antti Karttunen, <a href="/A213731/b213731.txt">Table of n, a(n) for n = 0..1024</a>

%F a(n) = 2*A079559(n) - A213719(n).

%o (Scheme): (define (A213731 n) (+ (A079559 n) (- (A079559 n) (A213719 n))))

%Y Cf. A179016, A213725, A213726, A213730.

%K nonn

%O 0,11

%A _Antti Karttunen_, Nov 01 2012