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 A113582 Triangle T(n,m) read by rows: T(n,m) = (n - m)*(n - m + 1)*m*(m + 1)/4 + 1. 3
 1, 1, 1, 1, 2, 1, 1, 4, 4, 1, 1, 7, 10, 7, 1, 1, 11, 19, 19, 11, 1, 1, 16, 31, 37, 31, 16, 1, 1, 22, 46, 61, 61, 46, 22, 1, 1, 29, 64, 91, 101, 91, 64, 29, 1, 1, 37, 85, 127, 151, 151, 127, 85, 37, 1, 1, 46, 109, 169, 211, 226, 211, 169, 109, 46, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS From Paul Barry, Jan 07 2009: (Start) This triangle follows a general construction method as follows: Let a(n) be an integer sequence with a(0)=1, a(1)=1. Then T(n,k,r) := [k<=n](1+r*a(k)*a(n-k)) defines a symmetrical triangle. Row sums are n + 1 + r*Sum_{k=0..n} a(k)*a(n-k) and central coefficients are 1+r*a(n)^2. Here a(n) = C(n+1,2) and r=1. Row sums are A154322 and central coefficients are A154323. (End) LINKS FORMULA T(n,m) = (n - m)*(n - m + 1)*m*(m + 1)/4 + 1. EXAMPLE {1}, {1, 1}, {1, 2, 1}, {1, 4, 4, 1}, {1, 7, 10, 7, 1}, {1, 11, 19, 19, 11, 1}, {1, 16, 31, 37, 31, 16, 1}, {1, 22, 46, 61, 61, 46, 22, 1}, {1, 29, 64, 91, 101, 91, 64, 29, 1}, {1, 37, 85, 127, 151, 151, 127, 85, 37, 1}, {1, 46, 109, 169, 211, 226, 211, 169, 109, 46, 1} MATHEMATICA t[n_, m_] = (n - m)*(n - m + 1)*m*(m + 1)/4 + 1; Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[%] PROG (MAGMA) /* As triangle: */ [[(n-m)*(n-m+1)*m*(m+1)/4+1: m in [0..n]]: n in [0.. 15]]; // Vincenzo Librandi, Sep 12 2016 CROSSREFS Sequence in context: A161126 A128562 A034368 * A118245 A104382 A086629 Adjacent sequences:  A113579 A113580 A113581 * A113583 A113584 A113585 KEYWORD nonn,tabl,easy AUTHOR Roger L. Bagula, Aug 25 2008 STATUS approved

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