Question 893319
this is an Arithmetic Sequence because the difference between one term and the next is a constant, and equal to {{{3}}}

in general we could write an arithmetic sequence like this:
{ {{{a}}}, {{{a+d}}}, {{{a+2d}}}, {{{a+3d}}}, ... }

{{{a = 1}}} (the first term) 
{{{d = 3}}} (the "common difference" between terms)

as a rule for any term:
{{{x[n] = a + d(n-1)}}} => we use "n-1" because d is not used in the 1st term

and calculate the 75th term 
{{{x[n] = a + d(n-1)}}}
{{{x[75] = 4 + 3(75-1)=4+3*74=4+222=226}}}