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 A203902 a(n)=f(a(n-1)+1,a(n-2)+1,a(n-3)+1), where f(x,y,z)=yz+zx+xy and (a(1),a(2),a(3))=(0,0,1). 2
 0, 0, 1, 5, 20, 180, 5013, 1016629, 5282300384, 5396635591915760, 28512136651893281578375965, 153869762066843605647265362776201153415021, 4387155683474529138873327728747664927423052537019723373711103123120 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS For a guide to related sequences, see A203761. LINKS MATHEMATICA a[1] = 0; a[2] = 0; a[3] = 1; a[n_] := SymmetricPolynomial[2, {1 + a[n - 1], 1 + a[n - 2], 1 + a[n - 3]}] Table[a[n], {n, 1, 13}]  (* A203902 *) CROSSREFS Cf. A203761. Sequence in context: A197857 A197741 A189317 * A000877 A203113 A077817 Adjacent sequences:  A203899 A203900 A203901 * A203903 A203904 A203905 KEYWORD nonn AUTHOR Clark Kimberling, Jan 07 2012 STATUS approved

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Last modified September 25 09:40 EDT 2021. Contains 347654 sequences. (Running on oeis4.)