A084769 - cp's OEIS frontend

A084769 a(n) = P_n(9), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 9x + 20x^2)^n.

n	a(n)
0	1
1	9
2	121
3	1809
4	28401
5	458649
6	7544041
7	125700129
8	2114588641
9	35836273449
10	610897146201
11	10463745263409
12	179939616743121
13	3104680678772409
14	53721299280288201
15	931852905510160449
16	16198821321758152641

[1, 9, 121, 1809, 28401, 458649, 7544041, 125700129, 2114588641, 35836273449, 610897146201, 10463745263409, 179939616743121, 3104680678772409, 53721299280288201, 931852905510160449, 16198821321758152641]

cp's OEIS Frontend

A084769 a(n) = P_n(9), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 9x + 20x^2)^n.

Table of values

List of values

cp's OEIS Frontend

A084769 a(n) = P_n(9), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 9*x + 20*x^2)^n.

Table of values

List of values

A084769 a(n) = P_n(9), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 9x + 20x^2)^n.