Prove that the arithmetic sequence with first term `1//3` and common difference `1//6` contain all natural numbers.

In an arithmetic Sequence, if T_4=8 & a=2 , then is common difference is:

Find the 10th term of an arithmetic progression whose first term is 'd' and common difference is 'b'.

If s_1,s_2,s_3 denote the sum of n terms of 3 arithmetic series whose first terms are unity and their common difference are in H.P., Prove that n=(2s_3s_1-s_1s_2-s_2s_3)/(s_1-2s_2+s_3)