Use Mathematical Induction to Prove That for All Positive Integers $n, 7+13+19+25+\cdots+(6 n+1)=3 n^{2}+4 n$

Short Answer

Use mathematical induction to prove that for all positive integers $n, 7+13+19+25+\cdots+(6 n+1)=3 n^{2}+4 n$ .