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 A135871 Triangle by columns: A013610 signed and interleaved with zeros. 1
 1, 0, 3, -1, 0, 9, 0, -6, 0, 27, 1, 0, -27, 0, 81, 0, 9, 0, -108, 0, 243, -1, 0, 54, 0, -405, 0, 729, 0, -12, 0, 270, 0, -1458, 0, 2187 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row sums = even indexed Fibonacci numbers, A001906: (1, 3, 8, 21, 55,...) such that the sum of n-th row terms = F(2n). Example: sum of nonzero terms of row 4 = (- 6 + 27) = 21 = F(8). LINKS FORMULA The triangle starts with A013610, then by columns sign (+, -, +,...) and interleave with zeros. EXAMPLE First few rows of the triangle are: 1; 0, 3; -1, 0, 9; 0, -6, 0, 27; 1, 0, -27, 0, 81; 0, 9, 0, -108, 0, 243; -1, 0, 54, 0, -405, 0, 729; ... CROSSREFS Cf. A013610, A001906. Sequence in context: A078521 A194938 A299614 * A126178 A094753 A221713 Adjacent sequences:  A135868 A135869 A135870 * A135872 A135873 A135874 KEYWORD tabl,sign AUTHOR Gary W. Adamson, Dec 02 2007 STATUS approved

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Last modified September 25 23:09 EDT 2021. Contains 347664 sequences. (Running on oeis4.)