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 A132898 Triangle read by rows: T(n,k) = (-1)^(n-1)*n + (-1)^(k-1)*k - 1, 1 <= k <= n. 2
 1, -2, -5, 3, 0, 5, -4, -7, -2, -9, 5, 2, 7, 0, 9, -6, -9, -4, -11, -2, -13, 7, 4, 9, 2, 11, 0, 13, -8, -11, -6, -13, -4, -15, -2, -17, 9, 6, 11, 4, 13, 2, 15, 0, 17, -10, -13, -8, -15, -6, -17, -4, -19, -2, -21, 11, 8, 13, 6, 15, 4, 17, 2, 19, 0, 21 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A132899: (1, -7, 8, -22, 23, -45,...) LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1275 (first 50 rows) EXAMPLE First few rows of the triangle are:    1;   -2,  -5;    3,   0,  5;   -4,  -7, -2,  -9;    5,   2,  7,   0,  9;   -6,  -9, -4, -11, -2, -13;    7,   4,  9,   2, 11,   0, 13;   -8, -11, -6, -13, -4, -15, -2, -17;    9,   6, 11,   4, 13,   2, 15,   0, 7;   ... T(5,3) = 7 = S(5) + S(3) = 5 + 3 - 1. PROG (PARI) T(n, k) = if(k<=n, (-1)^(n-1)*n + (-1)^(k-1)*k - 1, 0); \\ Andrew Howroyd, Sep 01 2018 CROSSREFS Row sums are A132899. Cf. A127648. Sequence in context: A160127 A011035 A102892 * A265318 A279536 A269954 Adjacent sequences:  A132895 A132896 A132897 * A132899 A132900 A132901 KEYWORD tabl,sign AUTHOR Gary W. Adamson, Sep 03 2007 EXTENSIONS Name clarified and terms a(56) and beyond from Andrew Howroyd, Sep 01 2018 STATUS approved

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Last modified May 23 05:03 EDT 2019. Contains 323508 sequences. (Running on oeis4.)