A246417 Homomorphic inverse images of elementary h-ary relations.

0, 0, 1, 7, 36, 171, 813, 4012, 25931, 342263, 6498746, 116477549, 1839530421, 26071946330, 339710531761, 4165394873379, 50578180795388, 717354862704287, 15348610400624113, 466529833772501084, 15332096138370552335

Offset

1,4

Comments

Corresponds to r_6(k) in the Rosenberg paper.

References

E. Ju. Zaharova, V. B. Kudrjavcev, and S. V. Jablonskii, Precomplete classes in k-valued logics. (Russian) Dokl. Akad. Nauk SSSR 186 (1969), 509-512. English translation in Soviet Math. Doklady 10 (No. 3, 1969), 618-622.

Links

Table of n, a(n) for n=1..21.

Ivo Rosenberg, The number of maximal closed classes in the set of functions over a finite domain, J. Combinatorial Theory Ser. A 14 (1973), 1-7.

Ivo Rosenberg and N. J. A. Sloane, Correspondence, 1971

E. Ju. Zaharova, V. B. Kudrjavcev, and S. V. Jablonskii, Precomplete classes in k-valued logics. (Russian), Dokl. Akad. Nauk SSSR 186 (1969), 509-512. English translation in Soviet Math. Doklady 10 (No. 3, 1969), 618-622. [Annotated scanned copy]

Formula

a(n) = Sum_{h^m <= k, h >= 3, m >= 1} (((-1)^h / (m! * (h!)^m)) * Sum_{L=1..h^m} (-1)^L * binomial(h^m, L) * L^n). - Sean A. Irvine, Aug 25 2014

Crossrefs

Cf. A002826.

Sequence in context: A099455 A102053 A058681 * A110310 A054493 A368575

Adjacent sequences: A246414 A246415 A246416 * A246418 A246419 A246420

Keyword

nonn

Author

Sean A. Irvine, Aug 25 2014

Status

approved