A085458 - cp's OEIS frontend

A085458 a(n) = 4Sum_{i=0..n-1} C(2i+1, i)C(n-1, n-1-i)(-1)^(n-1-i)*2^i for n > 0, a(0) = 1.

n	a(n)
0	1
1	4
2	20
3	116
4	708
5	4452
6	28532
7	185300
8	1215268
9	8030404
10	53381844
11	356577588
12	2391430020
13	16092704292
14	108605848116
15	734783381652
16	4982063186916
17	33844621986180
18	230306722637204
19	1569571734301172
20	10711405584991300

[1, 4, 20, 116, 708, 4452, 28532, 185300, 1215268, 8030404, 53381844, 356577588, 2391430020, 16092704292, 108605848116, 734783381652, 4982063186916, 33844621986180, 230306722637204, 1569571734301172, 10711405584991300]

cp's OEIS Frontend

A085458 a(n) = 4Sum_{i=0..n-1} C(2i+1, i)C(n-1, n-1-i)(-1)^(n-1-i)*2^i for n > 0, a(0) = 1.

Table of values

List of values

cp's OEIS Frontend

A085458 a(n) = 4*Sum_{i=0..n-1} C(2*i+1, i)*C(n-1, n-1-i)*(-1)^(n-1-i)*2^i for n > 0, a(0) = 1.

Table of values

List of values

A085458 a(n) = 4Sum_{i=0..n-1} C(2i+1, i)C(n-1, n-1-i)(-1)^(n-1-i)*2^i for n > 0, a(0) = 1.