A352280 - cp's OEIS frontend

A352280 a(0) = 1; a(n) = 3 * Sum_{k=0..floor((n-1)/2)} binomial(n-1,2k) a(n-2*k-1).

n	a(n)
0	1
1	3
2	9
3	30
4	117
5	516
6	2493
7	13152
8	75177
9	460272
10	3003921
11	20806176
12	152114013
13	1169842368
14	9435180357
15	79553524224
16	699531782481
17	6400932102912
18	60820145019801
19	599036357936640
20	6105903392066373
21	64309189153428480
22	698936466350352717
23	7828833281592926208
24	90270159223293364473

[1, 3, 9, 30, 117, 516, 2493, 13152, 75177, 460272, 3003921, 20806176, 152114013, 1169842368, 9435180357, 79553524224, 699531782481, 6400932102912, 60820145019801, 599036357936640, 6105903392066373, 64309189153428480, 698936466350352717, 7828833281592926208, 90270159223293364473]

cp's OEIS Frontend

A352280 a(0) = 1; a(n) = 3 * Sum_{k=0..floor((n-1)/2)} binomial(n-1,2k) a(n-2*k-1).

Table of values

List of values

cp's OEIS Frontend

A352280 a(0) = 1; a(n) = 3 * Sum_{k=0..floor((n-1)/2)} binomial(n-1,2*k) * a(n-2*k-1).

Table of values

List of values

A352280 a(0) = 1; a(n) = 3 * Sum_{k=0..floor((n-1)/2)} binomial(n-1,2k) a(n-2*k-1).