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T(n,k) = number of small equivalence classes of n-ary Boolean functions that contain 2^k functions.
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%I #15 Nov 02 2021 13:16:14

%S 2,2,1,2,3,2,2,7,14,23,2,15,70,345,3904

%N T(n,k) = number of small equivalence classes of n-ary Boolean functions that contain 2^k functions.

%C Left diagonal (k=0) has only 2s. Two functions (contradiction and tautology) are always alone in their respective sec, regardless of arity.

%C Second diagonal (k=1) is 2^n-1 (A000225). These are the n-ary linear Boolean functions. Each sec contains a row of a binary Walsh matrix and its complement.

%C Right diagonal (k=n) is A051502, the numbers of small equivalence classes of n-ary functions, that contain the highest possible number of 2^n functions.

%H Tilman Piesk, <a href="http://en.wikiversity.org/wiki/Equivalence_classes_of_Boolean_functions#sec">Small equivalence classes of Boolean functions</a>

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

%e Triangle begins: Row sums (A000231)

%e 2 2

%e 2 1 3

%e 2 3 2 7

%e 2 7 14 23 46

%e 2 15 70 345 3904 4336

%Y Cf. A000231, A051502, A000225, A227722.

%K nonn,tabl,more

%O 0,1

%A _Tilman Piesk_, Jul 22 2013