Question

find the first fie terms of the given recursively defined sequence: an=an-1 + an-2 + an-3 and a1 =a2=a3 = 1

Answer 1

plug n=4 and get a4,then plug n=5 and get a5

Answer 2

the formula
\[ \large a_n=a_{n-1}+a_{n-2}+a_{n-3} \]
tells u that any term of the sequence is the sum of the three previous terms
do u get this?