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a(n) = number of n-variable nondegenerate self-reflecting truth-tables.
1

%I #11 Mar 25 2021 16:02:33

%S 2,0,2,8,210,64384,4294577650,18446744043646148328,

%T 340282366920938463315800654962347229922,

%U 115792089237316195423570985008687907850207443363352117868951295327319990568640

%N a(n) = number of n-variable nondegenerate self-reflecting truth-tables.

%C A truth table is self-reflecting if the last column (the values of the function) is unchanged if it is reversed.

%H <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a>

%F a(0)=2; for n>0, a(n) = A000371(n-1)-a(n-1).

%e a(2)=2: The two nondegenerate self-reflecting truth tables are:

%e 0 0 : 0 1

%e 0 1 : 1 0

%e 1 0 : 1 0

%e 1 1 : 0 1

%Y Cf. A000371, A342287.

%K nonn

%O 0,1

%A _N. J. A. Sloane_, Mar 25 2021, based on an email from Nollaig MacKenzie, Mar 23 2021