A371818 - cp's OEIS frontend

A371818 a(n) = Sum_{k=0..floor(n/3)} (-1)^k * binomial(2n-2k,n-3*k).

n	a(n)
0	1
1	2
2	6
3	19
4	64
5	224
6	805
7	2947
8	10934
9	40975
10	154738
11	587910
12	2244681
13	8605061
14	33099767
15	127687258
16	493796454
17	1913755319
18	7431027611
19	28902878561
20	112585961052
21	439148770623
22	1715009647444
23	6705019714554
24	26240361155821
25	102787164654287
26	402972015656065

[1, 2, 6, 19, 64, 224, 805, 2947, 10934, 40975, 154738, 587910, 2244681, 8605061, 33099767, 127687258, 493796454, 1913755319, 7431027611, 28902878561, 112585961052, 439148770623, 1715009647444, 6705019714554, 26240361155821, 102787164654287, 402972015656065]

cp's OEIS Frontend

A371818 a(n) = Sum_{k=0..floor(n/3)} (-1)^k * binomial(2n-2k,n-3*k).

Table of values

List of values

cp's OEIS Frontend

A371818 a(n) = Sum_{k=0..floor(n/3)} (-1)^k * binomial(2*n-2*k,n-3*k).

Table of values

List of values

A371818 a(n) = Sum_{k=0..floor(n/3)} (-1)^k * binomial(2n-2k,n-3*k).