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 A128090 Denominators in inverse of A128077, numerators = 1. 1
 1, -4, 4, -18, -18, 9, -48, -48, -48, 16, -100, -100, -100, -100, 25, -180, -180, -180, -180, -180, 36, -294, -294, -294, -294, -294, -294, 49 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums of the inverse of A128077: (1/1; -1/4, 1/4; -1/18, -1/18, 1/9; ...) = (1, 0, 0, 0, ...). Row sums of unsigned terms: (1; 4, 4; 18, 18, 9; ...) = A128091. A045991 = (0, 0, 4, 18, 48, 100, ...). LINKS Table of n, a(n) for n=1..28. FORMULA Denominators in inverse triangular matrix of A128077, i.e., inverse of (1; 1, 4; 1, 2, 9; 1, 2, 3, 16; ...). EXAMPLE First few rows of the triangle: 1 -4, 4; -18, -18, 9; -48, -48, -48, 16; -100, -100, -100, -100, 25; ... CROSSREFS Cf. A128077, A045991, A128091. Sequence in context: A205110 A116561 A086448 * A119948 A005222 A214166 Adjacent sequences: A128087 A128088 A128089 * A128091 A128092 A128093 KEYWORD tabl,frac,sign,more AUTHOR Gary W. Adamson, Feb 14 2007 STATUS approved

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Last modified September 7 15:52 EDT 2024. Contains 375734 sequences. (Running on oeis4.)