A121680 - cp's OEIS frontend

A121680 a(n) = [x^n] (1 + x*(1+x)^(n+1) )^(n+1).

n	a(n)
0	1
1	2
2	12
3	76
4	655
5	6816
6	81690
7	1109816
8	16782399
9	278438740
10	5016899833
11	97368894756
12	2021749249403
13	44658312247290
14	1044437050070340
15	25757381769393392
16	667470006331599523
17	18119105978249333988

[1, 2, 12, 76, 655, 6816, 81690, 1109816, 16782399, 278438740, 5016899833, 97368894756, 2021749249403, 44658312247290, 1044437050070340, 25757381769393392, 667470006331599523, 18119105978249333988]

cp's OEIS Frontend

A121680 a(n) = [x^n] (1 + x*(1+x)^(n+1) )^(n+1).

Table of values

List of values