A378554 - cp's OEIS frontend

A378554 a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n+k-1,k) * binomial(k/2,n-k).

n	a(n)
0	1
1	1
2	7
3	28
4	171
5	846
6	4942
7	26580
8	153363
9	856900
10	4939682
11	28140476
12	162676878
13	936947116
14	5436375532
15	31526252208
16	183571246659
17	1069552636950
18	6247183319938
19	36524006501180
20	213899020967786
21	1253905101529080
22	7359775341696180
23	43237184121401400

[1, 1, 7, 28, 171, 846, 4942, 26580, 153363, 856900, 4939682, 28140476, 162676878, 936947116, 5436375532, 31526252208, 183571246659, 1069552636950, 6247183319938, 36524006501180, 213899020967786, 1253905101529080, 7359775341696180, 43237184121401400]

cp's OEIS Frontend

A378554 a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n+k-1,k) * binomial(k/2,n-k).

Table of values

List of values