7987616

Appears in sequences

• Array T(n,k) = number of conjugacy classes of subgroups of index k in free group of rank n, read by antidiagonals.at n=39A057004
• Number of conjugacy classes of subgroups of index 4 in free group of rank n.at n=5A057010
• Column 6 of array in A057004.at n=3A160871