Hello Math-Fun See those 3-digit (a, b and c) numbers as triangles with sides a, b and c: 111, 122,133,144,155,166,177,188,199, 212,221,222,223,244,... Is this (finite) seq in the OEIS? (I cannot compute its terms by hand -- all I know is that the biggest digit of n must be < the sum of the two others, like in 497). An equivalent seq could be computed for 4-gones numbers (starting with 1111,1112,1121,1211,... I guess), for 5-gones etc. Pardon me of this is old hat. Best, É.