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Number of complementary pairs of circulant graphs on n nodes.
2

%I #18 Jan 16 2022 22:09:20

%S 1,1,1,2,2,4,2,6,4,10,4,24,8,24,22,42,20,96,30,168,100,208,94,656,215,

%T 700,464,1552,596,4384,1096,4182,3384,8230,5572,23392,7316,29144,

%U 22212,68064,26272,177600,49940,216288,175712,381304,182362,1061472,399476

%N Number of complementary pairs of circulant graphs on n nodes.

%H Andrew Howroyd, <a href="/A054929/b054929.txt">Table of n, a(n) for n = 1..64</a>

%H V. A. Liskovets, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL3/LISK/Derseq.html">Some easily derivable sequences</a>, J. Integer Sequences, 3 (2000), #00.2.2.

%F Average of A049287 and A049289.

%F a(n) = A049287(n)/2 for n mod 4 <> 1; a(n) = (A049287(n) + A049289((n-1)/4))/2 for n mod 4 = 1. - _Andrew Howroyd_, Jan 16 2022

%Y Cf. A049287, A049289, A054930.

%K nonn

%O 1,4

%A _N. J. A. Sloane_, May 24 2000

%E Terms a(19) and beyond from _Andrew Howroyd_, Jan 16 2022