A216586 - cp's OEIS frontend

A216586 G.f.: exp( Sum_{n>=1} A002426(n)/2 * A002426(n) * x^n/n ), where A002426 is the central binomial coefficients and A002426 is the central trinomial coefficients.

n	a(n)
0	1
1	1
2	5
3	28
4	202
5	1579
6	13375
7	118858
8	1098458
9	10453452
10	101872926
11	1012109860
12	10218226307
13	104570617520
14	1082633236498
15	11321654913838
16	119438468577559
17	1269787015989428
18	13592294300856138
19	146390465351654178
20	1585337895099162317
21	17253991887494062080

[1, 1, 5, 28, 202, 1579, 13375, 118858, 1098458, 10453452, 101872926, 1012109860, 10218226307, 104570617520, 1082633236498, 11321654913838, 119438468577559, 1269787015989428, 13592294300856138, 146390465351654178, 1585337895099162317, 17253991887494062080]

cp's OEIS Frontend

A216586 G.f.: exp( Sum_{n>=1} A002426(n)/2 * A002426(n) * x^n/n ), where A002426 is the central binomial coefficients and A002426 is the central trinomial coefficients.

Table of values

List of values