Comments on A228351 Mikhail Kurkov Wed Dec 02 01:58:19 EST 2022 If T(n,k) is the formula for an irregular table from the Example section, so T(n,k) - 1 for k > 0 is the length of a continuous sequence of zeros between the k-th pair of ones from the right side in the binary representation of n. Here T(n, 0) - 1 is the length of a rightmost continuous sequence of zeros before the rightmost 1. T(2n+1,0) - 1 = 0 because the rightmost bit is 1. Formula for an irregular table from the Example section: T(n,k) = T(floor(n/2),k - n mod 2) for n > 1, k > 0 with T(n,0) = A001511(n) = 1 + (1 - n mod 2) * T(floor(n/2),0) for n > 1 with T(1,0)=1. In other words, T(2n,k) = T(n,k), T(2n+1,k) = T(n,k-1) for n > 1, k > 0, T(2n,0) = T(n,0) + 1 for n > 0, T(2n+1,0) = 1 for n >= 0.