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a = – 19, d = – 4

Let a₁ = a = – 19

Since, the common difference d = – 4

Using formula a_{n + 1} = a_n + d

Thus, a₂ = a₁ + d = – 19 + ( – 4) = – 19 – 4 = – 23

a_{3 =} a₂ + d = – 23 + ( – 4) = – 23 – 4 = – 27

a₄ = a₃ + d = – 27 + ( – 4) = – 27 – 4 = – 31

Hence, An A.P with common difference – 4 is – 19, – 23, – 27, – 31,….