Question 854996
Strange question.
The difference between consecutive terms of the sequence of perfect cubes are
7, 19, 37, 61, ....
The differences between consecutive differences are
{{{19-7=12}}}
{{{37-19=18}}}
{{{61-37=24}}}
and so on.
The differences of the differences, 12, 18, 24, ... form an arithmetic sequence.
Maybe that is the expected answer.