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A227725 T(n,k) = number of small equivalence classes of n-ary Boolean functions that contain 2^k functions. 1
2, 2, 1, 2, 3, 2, 2, 7, 14, 23, 2, 15, 70, 345, 3904 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

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

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.

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.

Triangle begins:              Row sums (A000231)

            2                         2

         2     1                      3

      2     3     2                   7

   2     7    14    23               46

2    15    70    345   3904        4336

LINKS

Table of n, a(n) for n=0..14.

Tilman Piesk, Small equivalence classes of Boolean functions

Index entries for sequences related to Boolean functions

CROSSREFS

A000231, A051502, A000225, A227722.

Sequence in context: A260414 A160735 A216338 * A331244 A316845 A120481

Adjacent sequences:  A227722 A227723 A227724 * A227726 A227727 A227728

KEYWORD

nonn,tabl,more

AUTHOR

Tilman Piesk, Jul 22 2013

STATUS

approved

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Last modified January 22 10:25 EST 2020. Contains 331144 sequences. (Running on oeis4.)