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H. L. Abbott and D. Hanson, A lattice path problem, Ars Combin., 6 (1978), 163-178.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Table of n, a(n) for n=3..10.
Sequence in context: A100442 A081126 A018191 * A149959 A161941 A120899
Adjacent sequences: A006188 A006189 A006190 * A006192 A006193 A006194
N. J. A. Sloane.