0905.php

<?php
declare (strict_types = 1);
// echo 'Proceed now';

function prepareOddAry($start, $end)
{
    $oddAry = [];
    do {
        if ($start === 1) {
            array_push($oddAry, $start);
        } else {
            ($start % 2 === 0) ? '' : array_push($oddAry, $start);
        }
        $start++;
    } while ($start <= $end);
    return $oddAry;
}

function rowSumOddNumbers(int $n): int
{
    $oddAry     = prepareOddAry(1, 2000);
    $startValue = $n * ($n - 1);

    $searchOddFromAry = ($startValue % 2 == 0) ? $startValue + 1 : $startValue;
    // echo $searchOddFromAry;

    $resultKey = array_search($searchOddFromAry, $oddAry);
    // echo $resultKey;

    $newSubAry = [];
    $a         = $resultKey;
    $i         = 0;
    do {
        array_push($newSubAry, $oddAry[$a]);
        $a++;
        $i++;
        // echo $i;
    } while ($i < $n);
    // print_r($newSubAry);
    return array_sum($newSubAry);
}
// echo rowSumOddNumbers(13);
// echo '</br>';
// print_r(prepareOddAry(1, 200));

echo pow(101, 3);