A256391 - cp's OEIS frontend

A256391 a(n) = number of tuples (a,b,c,d) of natural numbers a,b,c,d <= n with gcd(a,b)=gcd(b,c)=gcd(c,d)=gcd(d,a)=1.

n	a(n)
1	1
2	7
3	35
4	79
5	243
6	319
7	787
8	1155
9	1859
10	2295
11	4267
12	4891
13	8295
14	9743
15	11851
16	14539
17	22191
18	24359
19	35427
20	39387
21	45915
22	51687
23	71171
24	76407
25	94911
26	105047
27	123251
28	134447
29	174003
30	180835
31	229783
32	253007
33	281447
34	305111
35	343315
36	360215
37	442547
38	476115
39	523111
40	552307

[1, 7, 35, 79, 243, 319, 787, 1155, 1859, 2295, 4267, 4891, 8295, 9743, 11851, 14539, 22191, 24359, 35427, 39387, 45915, 51687, 71171, 76407, 94911, 105047, 123251, 134447, 174003, 180835, 229783, 253007, 281447, 305111, 343315, 360215, 442547, 476115, 523111, 552307]

cp's OEIS Frontend

A256391 a(n) = number of tuples (a,b,c,d) of natural numbers a,b,c,d <= n with gcd(a,b)=gcd(b,c)=gcd(c,d)=gcd(d,a)=1.

Table of values

List of values