algo solution for sup

solution.js

function conditionalRecursion(n) {
  if (n < 2) return n;
  return conditionalRecursion(n - 1) + conditionalRecursion(n - 2);
}

const tests = [
  [1, 3, 5, 7],
  [0, 1, 1, 2],
  [2, 4, 6, 8],
  [0, 1, 2, 3],
];

function testRecursion(tests) {
  tests.forEach((test, index) => {
    test.forEach(n => console.log(`test ${index} input: ${n} output: ${conditionalRecursion(n)}`));
  });
}
// run the script to get the outputs
testRecursion(tests);

Outputs:

test 0 input: 1 output: 1
test 0 input: 3 output: 2
test 0 input: 5 output: 5
test 0 input: 7 output: 13
test 1 input: 0 output: 0
test 1 input: 1 output: 1
test 1 input: 1 output: 1
test 1 input: 2 output: 1
test 2 input: 2 output: 1
test 2 input: 4 output: 3
test 2 input: 6 output: 8
test 2 input: 8 output: 21
test 3 input: 0 output: 0
test 3 input: 1 output: 1
test 3 input: 2 output: 1
test 3 input: 3 output: 2