A128620 Row sums of A128619.

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

Offset: 0

Author

Gary W. Adamson, Mar 14 2007

Keywords

• nonn
• easy

Comments

Diagonals sums of A199512. - Philippe Deléham, Dec 01 2013

Examples

			a(5) = 15 = sum of row 5 in A128619: (5 + 0 + 5 + 0 + 5).
		

Links

• G. C. Greubel, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (1,4,-3,-4,1,1).

Crossrefs

Cf. A000045, A128619, A199512.

Programs

Magma

[Floor((n+2)/2)*Fibonacci(n+1): n in [0..40]]; // G. C. Greubel, Mar 15 2024

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 *)

PARI

a(n)= ((n+2)\2) * fibonacci(n+1); \\ Michel Marcus, Dec 02 2013

SageMath

[int((n+2)/2)*fibonacci(n+1) for n in range(41)] # G. C. Greubel, Mar 15 2024

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

Extensions

More terms from Philippe Deléham, Dec 01 2013

a(31) corrected from Bruno Berselli, Dec 02 2013