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%I #50 Nov 05 2023 09:04:21
%S 2128,4689,7742,11011,11508,12277,16398,20227,22556,23709,26922,31455,
%T 36016,36857,39014,39563,45804,47213,47738,48847,48932,50805,53062,
%U 57575,58784,60281,63594,66251,68872,74021,79238,84175,89428,91709,92902,92947,94404,98317
%N Numbers k such that w(k), w(k+1), and w(k+2) are all odd, where w is A336957.
%C These terms are rare, since most of the time the parity of A336957 follows the pattern 1, 0,0, 1,1, 0,0, 1,1, 0,0, ... It would be useful to have a proof that the present sequence is (or is not) infinite. The graph strongly suggests it is an infinite sequence.
%C It is also possible that eventually there will be four or more odd terms in succession. However, this does not happen in the first eleven million terms, so probably it never happens.
%C If w(j) is even and w(j+1) is odd, then w(j+2) is forced to be also odd. In most cases w(j+3) is then even, but is occasionally odd (giving three odds in a row), and then the values of j+1 are given in the present sequence. For understanding the growth of A336957, the values of j+3 and w(j+3) are also important, and are given in A338070 and A338071, respectively.
%H N. J. A. Sloane, <a href="/A337644/b337644.txt">Table of n, a(n) for n = 1..5985</a> (computed from Frank Stevenson's file of the first 11333576 terms of A336957; terms 1..71 from N. J. A. Sloane, terms 72..575 from Scott R. Shannon)
%Y Cf. A336957, A338070, A338071.
%K nonn
%O 1,1
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Sep 24 2020
%E Comments revised by _N. J. A. Sloane_, Oct 12 2020
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