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a(n) is the number of odd terms in the n-th column of A334016.
1

%I #15 Oct 24 2020 17:19:34

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

%T 18,20,22,22,22,32,42,44,46,36,26,26,26,32,38,36,34,28,22,22,22,24,26,

%U 26,26,28,30,30,30,32,34,40,46,44,42,42,42,64,86,86,86,68

%N a(n) is the number of odd terms in the n-th column of A334016.

%C All terms are even.

%C Conjecture: a(2^n - 1) = 2^n for n > 0. - _Peter Kagey_, Oct 22 2020

%H Peter Kagey, <a href="/A338276/b338276.txt">Table of n, a(n) for n = 1..8192</a>

%H Peter Kagey, <a href="/A334016/a334016_1.png">Parity bitmap of first 2048 rows and 1024 columns of A334016.</a> (Even and odd entries and represented by black and white pixels respectively.)

%e Table for A334016 begins:

%e n\k| 1 2 3 4 5 6 7 8

%e ---+------------------------------------------------------------

%e 1| 1 1 6 35 237 1684 12557 96605

%e 2| 1 4 21 139 978 7239 55423 435550

%e 3| 2 10 65 451 3339 25559 200922 1611624

%e 4| 4 25 179 1337 10325 81716 658918 5394051

%e 5| 8 60 470 3725 30018 245220 2027447 16935981

%e 6| 16 140 1189 9958 83518 703635 5961973 50811786

%e 7| 32 320 2926 25802 224831 1951587 16938814 147261146

%e 8| 64 720 7048 65241 589701 5269220 46826316 415175289

%e a(1) = 2 because the first column has two odd values: (1,1).

%e a(2) = 2 because the second column has two odd values: (1,25).

%e a(3) = 4 because the third column has four odd values: (35,139,451,1337).

%Y Cf. A334016.

%Y Cf. A334001 is analogous for A279212.

%K nonn,look

%O 1,1

%A _Peter Kagey_, Oct 20 2020