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 A144181 INVERT transform of A118434, = row sums of triangle A144182. 4
 1, 1, 3, 9, 11, 17, 35, 57, 91, 161, 275, 457, 779, 1329, 2243, 3801, 6459, 10945, 18547, 31465, 53355, 90449, 153379, 260089, 440987, 747745, 1267923, 2149897, 3645387, 6181233, 10481027, 17771801, 30134267, 51096321, 86639923, 146908457, 249101099 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A118434 = row sums of the self-inverse triangle A118433 (a generator for the Rao Uppuluri-Carpenter numbers, A000587). A144181 = row sums of triangle A144182. LINKS Colin Barker, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (1,0,2). FORMULA Equals row sums of triangle A144182 and INVERT transform of A118434: (1, 0, 2, 4, -4, 0, -8, -16, 16, 0, 32,...). From Colin Barker, Aug 21 2016: (Start) a(n) = a(n-1)+2*a(n-3) for n>3. G.f.: (1+2*x^2+4*x^3) / (1-x-2*x^3). (End) EXAMPLE a(3) = 9 = sum of row 3 terms, triangle A144182: (4 + 2 + 0 + 3). PROG (PARI) Vec((1+2*x^2+4*x^3)/(1-x-2*x^3) + O(x^40)) \\ Colin Barker, Aug 21 2016 CROSSREFS Cf. A118434. Cf. A144182, A000587. Sequence in context: A227245 A173394 A111211 * A004626 A110999 A179867 Adjacent sequences:  A144178 A144179 A144180 * A144182 A144183 A144184 KEYWORD nonn,easy AUTHOR Gary W. Adamson, Sep 13 2008 EXTENSIONS More terms from Alois P. Heinz, May 23 2015 STATUS approved

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Last modified May 26 22:22 EDT 2020. Contains 334634 sequences. (Running on oeis4.)