A027317 - cp's OEIS frontend

A027317 a(n) = Sum_{k=0..m-2} T(n,k) * T(n,k+2), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.

n	a(n)
2	1
3	6
4	71
5	561
6	4797
7	41462
8	359530
9	3124752
10	27213084
11	237432807
12	2075064759
13	18162872365
14	159198909233
15	1397157808149
16	12275908402205
17	107974903916703
18	950639462501475
19	8377212510209165
20	73882962176311701
21	652114141845864819
22	5759883148706408695

[1, 6, 71, 561, 4797, 41462, 359530, 3124752, 27213084, 237432807, 2075064759, 18162872365, 159198909233, 1397157808149, 12275908402205, 107974903916703, 950639462501475, 8377212510209165, 73882962176311701, 652114141845864819, 5759883148706408695]

cp's OEIS Frontend

A027317 a(n) = Sum_{k=0..m-2} T(n,k) * T(n,k+2), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.

Table of values

List of values