A322228 - cp's OEIS frontend

A322228 a(n) = [x^n] Product_{k=1..n} (k + x - k*x^2), for n >= 0.

n	a(n)
0	1
1	1
2	-3
3	-21
4	75
5	1475
6	-5005
7	-221389
8	593523
9	57764619
10	-89101881
11	-23273632371
12	953636541
13	13409519997705
14	23908442020749
15	-10469975115603501
16	-40844292735050541
17	10646036726696597027
18	66995992524016223543
19	-13672657170891872702719
20	-122282221141986787179519
21	21647316686778755963070321
22	256325163531592225309743129
23	-41426918732532942751217361155
24	-620418821801458605268716606275
25	94275566307675915918535250768725

[1, 1, -3, -21, 75, 1475, -5005, -221389, 593523, 57764619, -89101881, -23273632371, 953636541, 13409519997705, 23908442020749, -10469975115603501, -40844292735050541, 10646036726696597027, 66995992524016223543, -13672657170891872702719, -122282221141986787179519, 21647316686778755963070321, 256325163531592225309743129, -41426918732532942751217361155, -620418821801458605268716606275, 94275566307675915918535250768725]

cp's OEIS Frontend

A322228 a(n) = [x^n] Product_{k=1..n} (k + x - k*x^2), for n >= 0.

Table of values

List of values