A026376 - cp's OEIS frontend

A026376 a(n) is the number of integer strings s(0),...,s(n) counted by array T in A026374 that have s(n)=2; also a(n) = T(2n,n-1).

n	a(n)
1	1
2	6
3	30
4	144
5	685
6	3258
7	15533
8	74280
9	356283
10	1713690
11	8263596
12	39938616
13	193419915
14	938430990
15	4560542550
16	22195961280
17	108171753355
18	527816696850
19	2578310320610
20	12607504827600
21	61706212037295
22	302275142049870
23	1481908332595625
24	7270432009471224

[1, 6, 30, 144, 685, 3258, 15533, 74280, 356283, 1713690, 8263596, 39938616, 193419915, 938430990, 4560542550, 22195961280, 108171753355, 527816696850, 2578310320610, 12607504827600, 61706212037295, 302275142049870, 1481908332595625, 7270432009471224]

cp's OEIS Frontend

A026376 a(n) is the number of integer strings s(0),...,s(n) counted by array T in A026374 that have s(n)=2; also a(n) = T(2n,n-1).

Table of values

List of values