A099511 - cp's OEIS frontend

A099511 Row sums of triangle A099510, so that a(n) = Sum_{k=0..n} coefficient of z^k in (1 + 2*z + z^2)^(n-[k/2]), where [k/2] is the integer floor of k/2.

n	a(n)
0	1
1	3
2	6
3	17
4	45
5	116
6	305
7	799
8	2090
9	5473
10	14329
11	37512
12	98209
13	257115
14	673134
15	1762289
16	4613733
17	12078908
18	31622993
19	82790071
20	216747218
21	567451585
22	1485607537
23	3889371024
24	10182505537
25	26658145587
26	69791931222
27	182717648081

[1, 3, 6, 17, 45, 116, 305, 799, 2090, 5473, 14329, 37512, 98209, 257115, 673134, 1762289, 4613733, 12078908, 31622993, 82790071, 216747218, 567451585, 1485607537, 3889371024, 10182505537, 26658145587, 69791931222, 182717648081]

cp's OEIS Frontend

A099511 Row sums of triangle A099510, so that a(n) = Sum_{k=0..n} coefficient of z^k in (1 + 2*z + z^2)^(n-[k/2]), where [k/2] is the integer floor of k/2.

Table of values

List of values