A383431 - cp's OEIS frontend

A383431 a(n) is the denominator of tanh(Sum_{k=1..n-1} artanh(k/n)), where artanh is the inverse hyperbolic tangent function.

n	a(n)
1	1
2	2
3	11
4	18
5	127
6	463
7	1717
8	3218
9	24311
10	92379
11	352717
12	1352079
13	5200301
14	20058301
15	77558761
16	150270098
17	1166803111
18	4537567651
19	17672631901
20	68923264411
21	269128937221
22	1052049481861
23	4116715363801
24	16123801841551
25	63205303218877
26	247959266474053
27	973469712824057
28	3824345300380221
29	15033633249770521

[1, 2, 11, 18, 127, 463, 1717, 3218, 24311, 92379, 352717, 1352079, 5200301, 20058301, 77558761, 150270098, 1166803111, 4537567651, 17672631901, 68923264411, 269128937221, 1052049481861, 4116715363801, 16123801841551, 63205303218877, 247959266474053, 973469712824057, 3824345300380221, 15033633249770521]

cp's OEIS Frontend

A383431 a(n) is the denominator of tanh(Sum_{k=1..n-1} artanh(k/n)), where artanh is the inverse hyperbolic tangent function.

Table of values

List of values