A370159 - cp's OEIS frontend

A370159 Coefficient of x^n in the expansion of ( (1+x) * (1+x+x^2)^2 )^n.

n	a(n)
0	1
1	3
2	19
3	132
4	963
5	7228
6	55264
7	428067
8	3347843
9	26378079
10	209065644
11	1664967747
12	13312423056
13	106798422942
14	859244421187
15	6930167382832
16	56015610380931
17	453628706358333
18	3679805451367471
19	29895358350622638
20	243204082036270588
21	1980931117038586824

[1, 3, 19, 132, 963, 7228, 55264, 428067, 3347843, 26378079, 209065644, 1664967747, 13312423056, 106798422942, 859244421187, 6930167382832, 56015610380931, 453628706358333, 3679805451367471, 29895358350622638, 243204082036270588, 1980931117038586824]

cp's OEIS Frontend

A370159 Coefficient of x^n in the expansion of ( (1+x) * (1+x+x^2)^2 )^n.

Table of values

List of values