| public static lucasNumber ( integer $n ) : array | ||
| $n | integer | How many numbers in the sequence |
| Результат | array | Indexed from 0 |
public static function lucasNumber(int $n) : array
{
$lucas = [];
// Bad input; return empty list
if ($n <= 0) {
return $lucas;
}
// Base case (n = 1): L₀ = 2
$lucas[] = 2;
if ($n === 1) {
return $lucas;
}
// Base case (n = 2): , L₀ = 2L₁ = 1
$lucas[] = 1;
if ($n === 2) {
return $lucas;
}
// Standard iterative case: Lᵢ = Lᵢ₋₁ + Lᵢ₋₂
for ($i = 2; $i < $n; $i++) {
$lucas[$i] = $lucas[$i - 1] + $lucas[$i - 2];
}
return $lucas;
}