A137637 - cp's OEIS frontend

A137637 a(n) = Sum_{k=0..n} C(2k+2,k)*C(2k+2,n-k) ; equals row 2 of square array A137634 ; also equals the convolution of A137635 and the self-convolution of A073157.

n	a(n)
0	1
1	6
2	32
3	170
4	899
5	4764
6	25318
7	134964
8	721562
9	3868024
10	20785035
11	111931154
12	603938905
13	3264309644
14	17671408012
15	95800342628
16	520022296700
17	2826089180652
18	15374990077568
19	83727902852188
20	456370687687082

[1, 6, 32, 170, 899, 4764, 25318, 134964, 721562, 3868024, 20785035, 111931154, 603938905, 3264309644, 17671408012, 95800342628, 520022296700, 2826089180652, 15374990077568, 83727902852188, 456370687687082]

cp's OEIS Frontend

A137637 a(n) = Sum_{k=0..n} C(2k+2,k)*C(2k+2,n-k) ; equals row 2 of square array A137634 ; also equals the convolution of A137635 and the self-convolution of A073157.

Table of values

List of values