Question 432068
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Hi
{3,6,9,12,...} d = 3  {{{a[n]=3+(n-1)3}}}, {{{a[100]=3+99*3 = 300}}}
{14,15,16,17,...} d = 1  {{{a[n]=14+(n-1)*1}}}, {{{a[100]=14+99 = 113}}}
{21,42,63,84,...} d = 21  {{{a[n]=21+(n-1)*21}}}, {{{a[100]=21+99*21 =2100}}}
{-10,-9,-8,-7,...} d = -1  {{{a[n]= -10+(n-1)*-1}}}, {{{a[100]=-10+99*-1 = -109}}}