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After zero, gives the numbers where finite "side-trees" (or "tendrils") of beanstalk branch off from its infinite trunk (A179016).
16

%I #21 Nov 05 2012 14:34:55

%S 0,2,5,6,9,10,14,17,18,22,27,30,33,34,38,43,47,48,52,56,62,65,66,70,

%T 75,79,80,84,88,95,96,100,105,108,113,117,121,126,129,130,134,139,143,

%U 144,148,152,159,160,164,169,172,177,181,185,191,192,196,201,204,208,214,220,224,230,237,241,246,254,257,258,262,267,271,272,276,280,287,288,292,297,300,305,309,313,319,320,324

%N After zero, gives the numbers where finite "side-trees" (or "tendrils") of beanstalk branch off from its infinite trunk (A179016).

%C These are the other branches branching off from the infinite trunk, than the ones that stay in that infinite trunk. These other branches are always finite, except for the zero in which case the other branch leads to 1, and the other branch (listed here) leads back to zero itself (as 0-A000120(0) = 0).

%C The terms include also those leaves (i.e. those terms of A055938) that are right next to the infinite trunk.

%H Antti Karttunen, <a href="/A213730/b213730.txt">Table of n, a(n) for n = 0..8727</a>

%F a(n) = A213723(A179016(n)) + A213728(n+1).

%F a(n) = A179016(n+1) + (-1)^A213729(n+1).

%o (Scheme): (define (A213730 n) (+ (A213723 (A179016 n)) (A213728 (1+ n))))

%o ;; Alternative definition:

%o (define (A213730v2 n) (+ (A179016 (1+ n)) (expt -1 (A213729 (1+ n)))))

%Y Cf. A218548.

%K nonn

%O 0,2

%A _Antti Karttunen_, Nov 01 2012

%E Offset changed from 1 to 0 by _Antti Karttunen_, Nov 05 2012