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%I #21 Mar 15 2024 03:41:32
%S 1,1,4,6,15,24,52,84,170,275,534,864,1631,2639,4880,7896,14373,23256,
%T 41810,67650,120406,194821,343884,556416,975325,1578109,2749852,
%U 4449354,7713435,12480600,21540304,34852944,59917826,96949079,166094370,268746336
%N Row sums of A128619.
%C Diagonals sums of A199512. - _Philippe Deléham_, Dec 01 2013
%H G. C. Greubel, <a href="/A128620/b128620.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,4,-3,-4,1,1).
%F a(n) = floor((n+2)/2)*Fibonacci(n+1). - _Philippe Deléham_, Dec 01 2013
%F G.f.: (1 - x^2 + x^3)/((1 + x - x^2)*(1 - x - x^2)^2). - _Bruno Berselli_, Dec 02 2013
%e a(5) = 15 = sum of row 5 in A128619: (5 + 0 + 5 + 0 + 5).
%t LinearRecurrence[{1,4,-3,-4,1,1}, {1,1,4,6,15,24}, 40] (* or *)
%t Table[Floor[(n+2)/2] Fibonacci[n+1], {n, 0, 40}] (* _Bruno Berselli_, Dec 02 2013 *)
%o (PARI) a(n)= ((n+2)\2) * fibonacci(n+1); \\ _Michel Marcus_, Dec 02 2013
%o (Magma) [Floor((n+2)/2)*Fibonacci(n+1): n in [0..40]]; // _G. C. Greubel_, Mar 15 2024
%o (SageMath) [int((n+2)/2)*fibonacci(n+1) for n in range(41)] # _G. C. Greubel_, Mar 15 2024
%Y Cf. A000045, A128619, A199512.
%K nonn,easy
%O 0,3
%A _Gary W. Adamson_, Mar 14 2007
%E More terms from _Philippe Deléham_, Dec 01 2013
%E a(31) corrected from _Bruno Berselli_, Dec 02 2013
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