808 Sums of powers of natural numbers
Exercise
1.Find the sum of the firstnodd numbers.2.Find the sum of the cubes of the firstnodd numbers.3.FindS 5 (n)andS 6 (n).4.Find the sum of the series1 · 2 ·3+2· 3 ·4+3· 4 ·5+···+n(n+1)(n+2).5.Find the sum of the firstntriangular numbers.