2124999

Appears in sequences

• Triangle T(n,k) = 10^(n-1) -1 + k*floor(9*10^(n-1)/(n+1)), with 1 <= r <= n, read by rows.at n=21A093850
• a(n) = A002283(n-1) + floor(A052268(n)/(1+n)).at n=6A093851