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 A039971 An example of a d-perfect sequence. 1
 1, 1, 2, 0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 2, 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 2, 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 1, 2, 0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS D. Kohel, S. Ling and C. Xing, Explicit Sequence Expansions, in Sequences and their Applications, C. Ding, T. Helleseth, and H. Niederreiter, eds., Proceedings of SETA'98 (Singapore, 1998), 308-317, 1999. DOI: 10.1007/978-1-4471-0551-0_23 FORMULA a(n) = ((-1)^(n+1)*A007317(n)) mod 3 - Christian G. Bower, Jun 12 2005 a(n) = A001405(n-1) mod 3. - John M. Campbell, Jul 19 2016 MATHEMATICA Table[Mod[Binomial[n - 1, Floor[(n - 1)/2]], 3], {n, 120}] (* or *) Table[Function[n, Mod[-(-1)^(n + 1) Sum[Binomial[n, k] CatalanNumber@ k, {k, 0, n}], 3]][n - 1], {n, 120}] (* Michael De Vlieger, Jul 19 2016 *) PROG (MAGMA) [Binomial(n, Floor(n/2)) mod 3: n in [0..140]]; // Vincenzo Librandi, Jul 20 2016 CROSSREFS Sequence in context: A303065 A325406 A257900 * A205593 A277937 A334913 Adjacent sequences:  A039968 A039969 A039970 * A039972 A039973 A039974 KEYWORD nonn AUTHOR EXTENSIONS More terms from Christian G. Bower, Jun 12 2005 STATUS approved

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Last modified January 24 21:08 EST 2022. Contains 350565 sequences. (Running on oeis4.)