SuperSecretStepSquads.php

<?php

// https://youtu.be/NyR3Pbj6LfE

$number_of_members_to_find = 100;
$previous = 0;
$step_squad_members = array();

for($i = 1; $i < $number_of_members_to_find + 1; $i++){
    $previous = $previous + $i;
    $step_squad_members[] = $previous;    
}

echo "Step Squad Members:" . PHP_EOL;
var_dump($step_squad_members);

/*
Step Squad Members:
array(100) {
  [0]=>
  int(1)
  [1]=>
  int(3)
  [2]=>
  int(6)
  [3]=>
  int(10)
  [4]=>
  int(15)
  [5]=>
  int(21)
  [6]=>
  int(28)
  [7]=>
  int(36)
  [8]=>
  int(45)
  [9]=>
  int(55)
  [10]=>
  int(66)
  [11]=>
  int(78)
  [12]=>
  int(91)
  [13]=>
  int(105)
  [14]=>
  int(120)
  [15]=>
  int(136)
  [16]=>
  int(153)
  [17]=>
  int(171)
  [18]=>
  int(190)
  [19]=>
  int(210)
  [20]=>
  int(231)
  [21]=>
  int(253)
  [22]=>
  int(276)
  [23]=>
  int(300)
  [24]=>
  int(325)
  [25]=>
  int(351)
  [26]=>
  int(378)
  [27]=>
  int(406)
  [28]=>
  int(435)
  [29]=>
  int(465)
  [30]=>
  int(496)
  [31]=>
  int(528)
  [32]=>
  int(561)
  [33]=>
  int(595)
  [34]=>
  int(630)
  [35]=>
  int(666)
  [36]=>
  int(703)
  [37]=>
  int(741)
  [38]=>
  int(780)
  [39]=>
  int(820)
  [40]=>
  int(861)
  [41]=>
  int(903)
  [42]=>
  int(946)
  [43]=>
  int(990)
  [44]=>
  int(1035)
  [45]=>
  int(1081)
  [46]=>
  int(1128)
  [47]=>
  int(1176)
  [48]=>
  int(1225)
  [49]=>
  int(1275)
  [50]=>
  int(1326)
  [51]=>
  int(1378)
  [52]=>
  int(1431)
  [53]=>
  int(1485)
  [54]=>
  int(1540)
  [55]=>
  int(1596)
  [56]=>
  int(1653)
  [57]=>
  int(1711)
  [58]=>
  int(1770)
  [59]=>
  int(1830)
  [60]=>
  int(1891)
  [61]=>
  int(1953)
  [62]=>
  int(2016)
  [63]=>
  int(2080)
  [64]=>
  int(2145)
  [65]=>
  int(2211)
  [66]=>
  int(2278)
  [67]=>
  int(2346)
  [68]=>
  int(2415)
  [69]=>
  int(2485)
  [70]=>
  int(2556)
  [71]=>
  int(2628)
  [72]=>
  int(2701)
  [73]=>
  int(2775)
  [74]=>
  int(2850)
  [75]=>
  int(2926)
  [76]=>
  int(3003)
  [77]=>
  int(3081)
  [78]=>
  int(3160)
  [79]=>
  int(3240)
  [80]=>
  int(3321)
  [81]=>
  int(3403)
  [82]=>
  int(3486)
  [83]=>
  int(3570)
  [84]=>
  int(3655)
  [85]=>
  int(3741)
  [86]=>
  int(3828)
  [87]=>
  int(3916)
  [88]=>
  int(4005)
  [89]=>
  int(4095)
  [90]=>
  int(4186)
  [91]=>
  int(4278)
  [92]=>
  int(4371)
  [93]=>
  int(4465)
  [94]=>
  int(4560)
  [95]=>
  int(4656)
  [96]=>
  int(4753)
  [97]=>
  int(4851)
  [98]=>
  int(4950)
  [99]=>
  int(5050)
}
*/