A026377 - cp's OEIS frontend

A026377 a(n) = number of integer strings s(0),...,s(n) counted by array T in A026374 that have s(n)=4; also a(n) = T(2n,n-2).

n	a(n)
2	1
3	9
4	58
5	330
6	1770
7	9198
8	46928
9	236736
10	1185645
11	5909805
12	29362806
13	145570230
14	720606705
15	3563543025
16	17610412600
17	86989143480
18	429579843435
19	2121099312195
20	10472653252550
21	51708363376950
22	255326054688320
23	1260886172311524
24	6227515552731528
25	30762417293645400

[1, 9, 58, 330, 1770, 9198, 46928, 236736, 1185645, 5909805, 29362806, 145570230, 720606705, 3563543025, 17610412600, 86989143480, 429579843435, 2121099312195, 10472653252550, 51708363376950, 255326054688320, 1260886172311524, 6227515552731528, 30762417293645400]

cp's OEIS Frontend

A026377 a(n) = number of integer strings s(0),...,s(n) counted by array T in A026374 that have s(n)=4; also a(n) = T(2n,n-2).

Table of values

List of values