A026521 - cp's OEIS frontend

A026521 a(n) = T(n, n-1), T given by A026519. Also a(n) = number of integer strings s(0), ..., s(n), counted by T, such that s(n) = 1.

n	a(n)
1	1
2	1
3	4
4	6
5	19
6	33
7	98
8	180
9	526
10	990
11	2887
12	5502
13	16073
14	30863
15	90386
16	174456
17	512128
18	992304
19	2918954
20	5673140
21	16716998
22	32571858
23	96119927
24	187675644
25	554524660
26	1084649644
27	3208254571
28	6284986554
29	18607536319
30	36501029265

[1, 1, 4, 6, 19, 33, 98, 180, 526, 990, 2887, 5502, 16073, 30863, 90386, 174456, 512128, 992304, 2918954, 5673140, 16716998, 32571858, 96119927, 187675644, 554524660, 1084649644, 3208254571, 6284986554, 18607536319, 36501029265]

cp's OEIS Frontend

A026521 a(n) = T(n, n-1), T given by A026519. Also a(n) = number of integer strings s(0), ..., s(n), counted by T, such that s(n) = 1.

Table of values

List of values