A278050 - cp's OEIS frontend

A278050 Let v = list of denominators of Farey series of order n (see A006843); let b(n) = Sum 1/(k+k'), where (k,k') are pairs of successive terms of v; a(n) = numerator of b(n).

n	a(n)
1	1
2	2
3	9
4	38
5	347
6	4189
7	11767
8	1733
9	1548081
10	31464371
11	14680543
12	353517989
13	3350216417
14	10571768267
15	2114915577977
16	69039991480573
17	538250871701
18	110983833313
19	328448743696081
20	48484885139543
21	553270527392631611
22	2736415713954900433
23	286367762285513933
24	2754025786313797907

[1, 2, 9, 38, 347, 4189, 11767, 1733, 1548081, 31464371, 14680543, 353517989, 3350216417, 10571768267, 2114915577977, 69039991480573, 538250871701, 110983833313, 328448743696081, 48484885139543, 553270527392631611, 2736415713954900433, 286367762285513933, 2754025786313797907]

cp's OEIS Frontend

A278050 Let v = list of denominators of Farey series of order n (see A006843); let b(n) = Sum 1/(k+k'), where (k,k') are pairs of successive terms of v; a(n) = numerator of b(n).

Table of values

List of values