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 A117425 Triangle T, read by rows, formed by a column bisection of triangle A117418: column k of T equals column 2*k of A117418. 3
 1, 1, 1, 1, 3, 1, 1, 8, 5, 1, 1, 22, 20, 7, 1, 1, 65, 79, 37, 9, 1, 1, 208, 322, 180, 58, 11, 1, 1, 723, 1385, 871, 339, 83, 13, 1, 1, 2721, 6293, 4296, 1935, 550, 113, 15, 1, 1, 11053, 30152, 21821, 11092, 3465, 846, 148, 17, 1, 1, 48220, 151842, 114676, 64748, 21514 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 LINKS EXAMPLE Triangle begins: 1; 1, 1; 1, 3, 1; 1, 8, 5, 1; 1, 22, 20, 7, 1; 1, 65, 79, 37, 9, 1; 1, 208, 322, 180, 58, 11, 1; 1, 723, 1385, 871, 339, 83, 13, 1; 1, 2721, 6293, 4296, 1935, 550, 113, 15, 1; 1, 11053, 30152, 21821, 11092, 3465, 846, 148, 17, 1; ... Column k of T equals column 2*k of A117418, which begins: 1; 1, 1; 1, 2, 1; 1, 4, 3, 1; 1, 9, 8, 4, 1; 1, 23, 22, 14, 5, 1; 1, 66, 65, 50, 20, 6, 1; 1, 209, 208, 191, 79, 28, 7, 1; ... Let matrix R = SHIFT_RIGHT(A117418): 1; 0, 1; 0, 1, 1; 0, 1, 2, 1; 0, 1, 4, 3, 1; 0, 1, 9, 8, 4, 1; 0, 1, 23, 22, 14, 5, 1; 0, 1, 66, 65, 50, 20, 6, 1; ... then the matrix product A117418*R yields this triangle. PROG (PARI) CROSSREFS Cf. A117426 (row sums); A117418, A117427 (dual). Sequence in context: A152879 A098747 A122897 * A287215 A168216 A091698 Adjacent sequences:  A117422 A117423 A117424 * A117426 A117427 A117428 KEYWORD nonn,tabl AUTHOR Paul D. Hanna, Mar 14 2006 STATUS approved

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Last modified May 21 02:57 EDT 2019. Contains 323434 sequences. (Running on oeis4.)