A322227 - cp's OEIS frontend

A322227 a(n) = [x^(n-1)] Product_{k=1..n} (k + x - k*x^2), for n >= 1.

n	a(n)
1	1
2	3
3	-12
4	-140
5	540
6	15456
7	-50932
8	-3176172
9	7343325
10	1053842295
11	-1009469538
12	-515714090814
13	-374961500823
14	349796118587475
15	949197425607720
16	-314320029983283752
17	-1565276549925545181
18	361569820089891813849
19	2715239099277372861920
20	-518323783521922446434520
21	-5333587428291215212424382
22	906157476001402934272328354
23	12062331313935951302447900940
24	-1897919702589547490476079347500
25	-31441371048822199544956413616625

[1, 3, -12, -140, 540, 15456, -50932, -3176172, 7343325, 1053842295, -1009469538, -515714090814, -374961500823, 349796118587475, 949197425607720, -314320029983283752, -1565276549925545181, 361569820089891813849, 2715239099277372861920, -518323783521922446434520, -5333587428291215212424382, 906157476001402934272328354, 12062331313935951302447900940, -1897919702589547490476079347500, -31441371048822199544956413616625]

cp's OEIS Frontend

A322227 a(n) = [x^(n-1)] Product_{k=1..n} (k + x - k*x^2), for n >= 1.

Table of values

List of values