if object_id (N'gc_pr_get_prime_num_combn', N'P') is not null
begin
    drop procedure gc_pr_get_prime_num_combn;
end
go

if object_id (N'gc_pr_rand_as_string', N'P') is not null
begin
    drop procedure gc_pr_rand_as_string;
end
go

if object_id (N'gc_pr_gb_pair_rm', N'P') is not null
begin
    drop procedure gc_pr_gb_pair_rm;
end
go