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 A007159 Essentially n-ary operations in a certain 3-element algebra. (Formerly M2767) 0
 3, 8, 178, 129054, 430903911398 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 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) FORMULA a(n) = Sum_{i=0..n} (-1)^(n-i) * binomial(n, i) * A007156(i). - Sean A. Irvine, Nov 05 2017 CROSSREFS Cf. A007156. Sequence in context: A076147 A132563 A065061 * A081466 A092592 A162185 Adjacent sequences:  A007156 A007157 A007158 * A007160 A007161 A007162 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 14 09:41 EST 2019. Contains 329979 sequences. (Running on oeis4.)