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The number of odd values in the n-th column of A279212.
2

%I #15 Oct 05 2020 01:02:06

%S 2,2,4,4,6,8,8,10,10,12,16,12,16,14,18,12,22,24,20,16,22,22,24,26,22,

%T 26,28,16,30,30,36,24,34,36,32,30,30,44,42,44,38,44,50,34,44,46,54,36,

%U 50,60,56,30,50,56,56,46,54,56,68,36,68,54,56,46,44,66,54

%N The number of odd values in the n-th column of A279212.

%C All of the values in this sequence are even, as shown in Alec Jones's proof that each column of A279212 has a finite number of odd entries.

%C Conjecture: a(n) <= 2*n.

%H Peter Kagey, <a href="/A334001/b334001.txt">Table of n, a(n) for n = 1..1024</a>

%H Alec Jones, <a href="/A279212/a279212.pdf">Proof that columns of A279212 have finitely many odd entries</a>.

%H Peter Kagey, <a href="/A279212/a279212.png">Bitmap showing parity of first 1024 rows and 512 columns of A269212</a>. (Odd values are white; even values are black.)

%e For n = 3, the third column of A279212 is 11, 39, 119, 330, 870, 2209, 5454, 13176, 31280, 73200, ... which contains a(3) = 4 odd values.

%Y Cf. A279212.

%K nonn

%O 1,1

%A _Peter Kagey_, Apr 12 2020