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 A145580 Eigentriangle, row sums = A000930 2
 1, 1, 1, 0, 1, 2, -1, 0, 2, 3, 0, -1, 0, 3, 4, 1, 0, -2, 0, 4, 6, 0, 1, 0, -3, 0, 6, 9, -1, 0, 2, 0, -4, 0, 9, 13, 0, -1, 0, 3, 0, -6, 0, 13, 19, 1, 0, -2, 0, 4, 0, -9, 0, 19, 28 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS Row sums = A000930 starting with offset 1: (1, 1, 2, 3, 4, 6, 9, 13, 19,...). Sum of n-th row terms = rightmost term of next row. LINKS FORMULA Let M = an infinite lower triangular matrix with (1, 1, 0, -1, 0, 1, 0, -1, 0, 1,...) in every column; and X = an infinite lower triangular matrix with A000930 as the main diagonal (offset 1): (1, 1, 2, 3, 4, 6, 9, 13, 19,...) and the rest zeros. Triangle A145580 = M * X. EXAMPLE First few rows of the triangle = 1; 1, 1; 0, 1, 2; -1, 0, 2, 3; 0, -1, 0, 3, 4; 1, 0, -2, 0, 4, 6; 0, 1, 0, -3, 0, 6, 9; -1, 0, 2, 0, -4, 0, 9, 13; 0, -1, 0, 3, 0, -6, 0, 13, 19; 1, 0, -2, 0, 4, 0, -9, 0, 19, 28; ... Row 6 = (1, 0, -2, 0, 4, 6) = termwise products of (1, 0, -1, 0, 1, 1) and (1, 1, 2, 3, 4, 6). CROSSREFS Sequence in context: A308321 A097854 A161515 * A144219 A144027 A019591 Adjacent sequences:  A145577 A145578 A145579 * A145581 A145582 A145583 KEYWORD tabl,sign AUTHOR Gary W. Adamson, Oct 13 2008 STATUS approved

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Last modified May 16 10:30 EDT 2021. Contains 343941 sequences. (Running on oeis4.)