$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$wp_query= null;
$wp_query = new WP_Query();
$args = array(
    'showposts' => 20,
    'paged' => $paged,
    'ignore_sticky_posts' => 1
);
$wp_query->query($args);
while ($wp_query->have_posts()) : $wp_query->the_post();
include 'post.php';
endwhile;
global $wp_query;
$big = 999999999; // need an unlikely integer
echo paginate_links( array(
    'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
    'format' => '?paged=%#%',
    'current' => max( 1, get_query_var('paged') ),
    'total' => $wp_query->max_num_pages
) );