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 A123934 Triangle T(n,k), 1<=k<=n :forms the odd-indexed trinomial coefficients (A027907). 0
 1, 2, 2, 3, 7, 3, 4, 16, 16, 4, 5, 30, 51, 30, 5, 6, 50, 126, 126, 50, 6, 7, 77, 266, 393, 266, 77, 7 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA Sum_{k, 1<=k<=n}T(n,k)=A003462(n)=(3^n-1)/2. EXAMPLE Triangle begins: 1; 2, 2; 3, 7, 3; 4, 16, 16, 4; 5, 30, 51, 30, 5; 6, 50, 126, 126, 50, 6; 7, 77, 266, 393, 266, 77, 7; CROSSREFS Cf. A056241. Sequence in context: A183442 A296019 A134232 * A208151 A203362 A183407 Adjacent sequences:  A123931 A123932 A123933 * A123935 A123936 A123937 KEYWORD nonn,tabl AUTHOR Philippe Deléham, Oct 30 2006 STATUS approved

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Last modified September 24 12:28 EDT 2021. Contains 347642 sequences. (Running on oeis4.)