A278046 - cp's OEIS frontend

A278046 Let v = list of denominators of Farey series of order n (see A006843); a(n) = sum of products of adjacent terms of v.

n	a(n)
1	1
2	4
3	18
4	44
5	124
6	186
7	424
8	636
9	1038
10	1378
11	2368
12	2852
13	4516
14	5510
15	7030
16	8734
17	12542
18	14168
19	19526
20	22206
21	26658
22	30728
23	40342
24	44190
25	54590
26	61402
27	72328
28	80196
29	99684
30	105644
31	129514
32	143162
33	161422
34	176926
35	201566
36	214538
37	255386
38	277160
39	307736
40	329096
41	384856
42	402412
43	466826
44	499166

[1, 4, 18, 44, 124, 186, 424, 636, 1038, 1378, 2368, 2852, 4516, 5510, 7030, 8734, 12542, 14168, 19526, 22206, 26658, 30728, 40342, 44190, 54590, 61402, 72328, 80196, 99684, 105644, 129514, 143162, 161422, 176926, 201566, 214538, 255386, 277160, 307736, 329096, 384856, 402412, 466826, 499166]

cp's OEIS Frontend

A278046 Let v = list of denominators of Farey series of order n (see A006843); a(n) = sum of products of adjacent terms of v.

Table of values

List of values