PHP, 54 bytes

function($x){for(;$y<$x;$a[]=range(++$y,1));return$a;}

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Or recursive:

PHP, 54 bytes

function f($x){return$x?f($x-1)+[$x=>range($x,1)]:[];}

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PHP, 54 bytes

function($x){for(;$y<$x;$a[]=range(++$y,1));return$a;}

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Or recursive:

PHP, 54 bytes

function f($x){return$x?f($x-1)+[$x=>range($x,1)]:[];}

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Or with PHP-formatted printed output:

PHP , 38 bytes

for(;$x<$argn;print_r(range(++$x,1)));

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PHP, 54 bytes

function($x){for(;$y<$x;$a[]=range(++$y,1));return$a;}

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PHP, 54 bytes

function($x){for(;$y<$x;$a[]=range(++$y,1));return$a;}

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Or recursive:

PHP , 54 bytes

function f($x){return$x?f($x-1)+[$x=>range($x,1)]:[];}

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PHP, 64 bytes

function($x){foreach(range(1,$x)as$a)$b[]=range($a,1);return$b;}

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PHP, 54 bytes

function($x){for(;$y<$x;$a[]=range(++$y,1));return$a;}

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