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 A128620 Row sums of A128619. 2
 1, 1, 4, 6, 15, 24, 52, 84, 170, 275, 534, 864, 1631, 2639, 4880, 7896, 14373, 23256, 41810, 67650, 120406, 194821, 343884, 556416, 975325, 1578109, 2749852, 4449354, 7713435, 12480600, 21540304, 34852944, 59917826, 96949079, 166094370, 268746336 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Diagonals sums of A199512. - Philippe Deléham, Dec 01 2013 LINKS Index entries for linear recurrences with constant coefficients, signature (1,4,-3,-4,1,1). FORMULA a(n) = floor((n+2)/2)*Fibonacci(n+1). - Philippe Deléham, Dec 01 2013 G.f.: (1 - x^2 + x^3)/((1 + x - x^2)*(1 - x - x^2)^2). [Bruno Berselli, Dec 02 2013] EXAMPLE a(5) = 15 = sum of row 5 in A128619: (5 + 0 + 5 + 0 + 5). MATHEMATICA LinearRecurrence[{1, 4, -3, -4, 1, 1}, {1, 1, 4, 6, 15, 24}, 40] (* or *) Table[Floor[(n + 2)/2] Fibonacci[n + 1], {n, 0, 40}] (* Bruno Berselli, Dec 02 2013 *) PROG (PARI) a(n)= ((n+2)\2) * fibonacci(n+1); \\ Michel Marcus, Dec 02 2013 CROSSREFS Cf. A000045, A128619, A199512. Sequence in context: A300276 A109731 A027631 * A045907 A254325 A034299 Adjacent sequences:  A128617 A128618 A128619 * A128621 A128622 A128623 KEYWORD nonn,easy AUTHOR Gary W. Adamson, Mar 14 2007 EXTENSIONS More terms from Philippe Deléham, Dec 01 2013 a(31) corrected from Bruno Berselli, Dec 02 2013 STATUS approved

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Last modified December 6 09:10 EST 2021. Contains 349563 sequences. (Running on oeis4.)