Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A000616
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A000616 a(-1)=1 by convention; for n >= 0, a(n) = number of irreducible Boolean functions of n variables.
(Formerly M0819 N0310)
+0
17
1, 2, 3, 6, 22, 402, 1228158, 400507806843728, 527471432057653004017274030725792, 11218076601767519586965281984173341005925142853855481024470471657123840 (list; graph; listen)
OFFSET

-1,2

COMMENT

Number of NP-equivalence classes of switching functions of n or fewer variables.

Number of inequivalent binary nonlinear codes of length n (and all sizes).

a(n+1) = number of NPN-equivalence classes of canalizing functions (see A102449) with n variables. NPN-equivalence allows complementing the function value as well as the individual variables. E.g. The 6 inequivalent canalizing functions when n=3 are 0, x, x AND y, x AND y AND z, x AND (y OR z), x AND (y XOR z). - D. E. Knuth, Aug 24 2005, Aug 06 2006

REFERENCES

F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 112.

M. A. Harrison, The number of transitivity sets of Boolean functions, J. Soc. Indust. Appl. Math., 11 (1963), 806-828.

M. A. Harrison, Introduction to Switching and Automata Theory. McGraw Hill, NY, 1965, p. 149.

D. E. Knuth, The Art of Computer Programming, Vol. 4, Section 7.1.1 (in preparation).

S. Muroga, Threshold Logic and Its Applications. Wiley, NY, 1971, p. 38, Table 2.3.2. - Row 11.

J. Sklansky, General synthesis of tributary switching networks, IEEE Trans. Elect. Computers, 12 (1963), 464-469.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Index entries for sequences related to Boolean functions

FORMULA

Harrison givers a simple formula in terms of the cycle index of the appropriate group.

CROSSREFS

Row sums of A039754.

Cf. A102449, A109460, A109462.

Sequence in context: A094470 A015764 A015759 this_sequence A018300 A027163 A160683

Adjacent sequences: A000613 A000614 A000615 this_sequence A000617 A000618 A000619

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs)

Entry revised by N. J. A. Sloane (njas(AT)research.att.com), Aug 07 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


AT&T Labs Research