A007159 Essentially n-ary operations in a certain 3-element algebra.
3, 8, 178, 129054, 430903911398
Offset: 0
Keywords
References
- J. Berman, ``Free spectra of 3-element algebras,'' in R. S. Freese and O. C. Garcia, editors, Universal Algebra and Lattice Theory (Puebla, 1982), Lect. Notes Math. Vol. 1004, 1983.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Links
- J. Berman, Free spectra of 3-element algebras, R. S. Freese and O. C. Garcia, editors, Universal Algebra and Lattice Theory (Puebla, 1982), Lect. Notes Math. Vol. 1004, 1983. (Annotated scanned copy)
Crossrefs
Cf. A007156.
Formula
a(n) = Sum_{i=0..n} (-1)^(n-i) * binomial(n, i) * A007156(i). - Sean A. Irvine, Nov 05 2017