A333500 A(n,k) is the n-th number m such that m^2 divides k^m - 1 (or 0 if m does not exist); square array A(n,k), n>=1, k>=1, read by antidiagonals.
1, 1, 2, 1, 0, 3, 1, 2, 0, 4, 1, 3, 4, 0, 5, 1, 2, 21, 20, 0, 6, 1, 5, 4, 903, 220, 0, 7, 1, 2, 1555, 6, 2667, 1220, 0, 8, 1, 7, 3, 9673655, 12, 7077, 2420, 0, 9, 1, 2, 889, 4, 187159211791705, 42, 113799, 5060, 0, 10, 1, 3, 4, 2359, 6, 776119592182705, 52, 114681, 13420, 0, 11
Offset: 1
Examples
Square array A(n,k) begins: 1, 1, 1, 1, 1, 1, ... 2, 0, 2, 3, 2, 5, ... 3, 0, 4, 21, 4, 1555, ... 4, 0, 20, 903, 6, 9673655, ... 5, 0, 220, 2667, 12, 187159211791705, ... 6, 0, 1220, 7077, 42, 776119592182705, ...