How to Compute a Cube as Sums in Golang

The challenge

You will be given a number n (where n >= 1) and your task is to find n consecutive odd numbers whose sum is exactly the cube of n.

Mathematically:
cube = n ** 3
sum = a1 + a2 + a3 + ….. + an
sum == cube
a2 == a1 + 2, a3 == a2 + 2, …….

For example:

FindSummands(3) == []int{7,9,11} // ..because 7 + 9 + 11 = 27, the cube of 3. // Note that there are only n = 3 elements in the array.
Code language: JavaScript (javascript)

Write function findSummands(n) which will return an array of n consecutive odd numbers with the sum equal to the cube of n (n*n*n).

The solution in Golang

Option 1:

package solution func FindSummands(n int) []int { res := []int{} y := n * n - n + 1 for i := 0; i<n; i++ { res = append(res, y + 2 * i) } return res }
Code language: Go (go)

Option 2:

package solution func FindSummands(n int) []int { a := n*n - n + 1 res := make([]int, n) for i := 0; i < n; i++ { res[i] = a + i*2 } return res }
Code language: Go (go)

Option 3:

package solution func FindSummands(n int) []int { a:=n*n-n+1; arr:=make([]int, n) for i:=0; i<n; i++ { arr[i] = a; a+=2 } return arr }
Code language: Go (go)

Test cases to validate our solution

package solution_test import ( "fmt" . "github.com/onsi/ginkgo" . "github.com/onsi/gomega" ) var _ = Describe("Example Tests: 1 through 4",func() { test_sols := [...][]int{ []int{1}, []int{3,5}, []int{7,9,11}, []int{13,15,17,19}, } for i,v := range []int{1,2,3,4} { It(fmt.Sprintf("test for number %d",v),func() { num := FindSummands(v) Expect(num).To(Equal(test_sols[i]))}) } })
Code language: Go (go)
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