Summary Sequences and Series formula sheet

Sequences and Series Formula Sheet

1. The nth term (general term) of the A.P.:
𝑎𝑛 = 𝑎 + (𝑛 − 1)𝑑
Where a = First term
d = Common difference
• If A.P. (in its standard form) with first term a and
common difference d, i.e., a, a + d, a + 2d, ...
• If a constant is added to each term of an A.P., the
resulting sequence is also an A.P.
• If a constant is subtracted from each term of an
A.P., the resulting sequence is also an A.P.
• If each term of an A.P. is multiplied by a constant,
then the resulting sequence is also an A.P.
• If each term of an A.P. is divided by a non-zero
constant then the resulting sequence is also an A.P.
• Let a, a + d, a + 2d, …, a + (n – 1) d be an A.P. Then
l = a + (n – 1) d

where a = First term
l = Last term
n = no. of terms
d = Common difference
𝑠𝑛 = Sum of n terms of A.P