A005774 - cp's OEIS frontend

A005774 Number of directed animals of size n (k=1 column of A038622); number of (s(0), s(1), ..., s(n)) such that s(i) is a nonnegative integer and |s(i) - s(i-1)| <= 1 for i = 1,2,...,n, where s(0) = 2; also sum of row n+1 of array T in A026323.

n	a(n)
0	0
1	1
2	3
3	9
4	26
5	75
6	216
7	623
8	1800
9	5211
10	15115
11	43923
12	127854
13	372749
14	1088283
15	3181545
16	9312312
17	27287091
18	80038449
19	234988827
20	690513030
21	2030695569
22	5976418602
23	17601021837
24	51869858544
25	152951628725
26	451271872701
27	1332147482253

[0, 1, 3, 9, 26, 75, 216, 623, 1800, 5211, 15115, 43923, 127854, 372749, 1088283, 3181545, 9312312, 27287091, 80038449, 234988827, 690513030, 2030695569, 5976418602, 17601021837, 51869858544, 152951628725, 451271872701, 1332147482253]

cp's OEIS Frontend

A005774 Number of directed animals of size n (k=1 column of A038622); number of (s(0), s(1), ..., s(n)) such that s(i) is a nonnegative integer and |s(i) - s(i-1)| <= 1 for i = 1,2,...,n, where s(0) = 2; also sum of row n+1 of array T in A026323.

Table of values

List of values