A215973 - cp's OEIS frontend

A215973 a(0) = 1, for n > 0: a(n) = Sum_{k=0..n-1} a(k) * (1 + a(n-1-k)).

n	a(n)
0	1
1	2
2	7
3	28
4	122
5	565
6	2735
7	13682
8	70188
9	367248
10	1952394
11	10516141
12	57265929
13	314751625
14	1743829163
15	9728561418
16	54604800126
17	308137127382
18	1747158309208
19	9949001656704
20	56872435967840
21	326243091718978
22	1877419829207578
23	10835354636496321

[1, 2, 7, 28, 122, 565, 2735, 13682, 70188, 367248, 1952394, 10516141, 57265929, 314751625, 1743829163, 9728561418, 54604800126, 308137127382, 1747158309208, 9949001656704, 56872435967840, 326243091718978, 1877419829207578, 10835354636496321]

cp's OEIS Frontend

A215973 a(0) = 1, for n > 0: a(n) = Sum_{k=0..n-1} a(k) * (1 + a(n-1-k)).

Table of values

List of values