United States Court of Appeals
                            For the Eighth Circuit
                        ___________________________

                                No. 13-2213
                        ___________________________

                             United States of America

                        lllllllllllllllllllll Plaintiff - Appellee

                                           v.

                                   Lucas Robinson

                      lllllllllllllllllllll Defendant - Appellant
                                      ____________

                     Appeal from United States District Court
                 for the Northern District of Iowa - Cedar Rapids
                                  ____________

                          Submitted: December 20, 2013
                             Filed: January 24, 2014
                                 [Unpublished]
                                 ____________

Before MURPHY, BYE, and SMITH, Circuit Judges.
                           ____________

PER CURIAM.

       Lucas Robinson appeals his sentence of 504 months following his guilty plea
to one count of sexual exploitation of a minor, one count of possession of child
pornography, and one count of extortion. While the advisory guidelines range for
Robinson's offense was life imprisonment, the statutory maximum sentences for the
three charges to which he pleaded guilty were collectively forty-two years (thirty
years for the sexual exploitation charge, ten years for the child pornography charge,
and two years for the extortion charge), effectively making Robinson's advisory
guidelines range 504 months. See United States Sentencing Guidelines Manual
(U.S.S.G.) § 5G1.2. The district court1 thus stayed within the guidelines by imposing
a sentence of 504 months.

       On appeal, Robinson argues his sentence is substantively unreasonable.
Reviewing for an abuse of discretion, United States v. Jones, 

, 1044
(8th Cir. 2010), we find none. Our review of the record indicates the district court
properly considered the 18 U.S.C. § 3553(a) factors and chose to impose a within-
guidelines sentence, which we conclude is presumptively reasonable. See United
States v. Never Misses a Shot, 

, 1054 (8th Cir. 2013). In addition, the
district court considered Robinson's requests for a downward departure and for a
variance, recognized it had the authority to depart or vary, but simply declined to do
so. Robinson fails to identify anything in particular to indicate the district court
abused its discretion in refusing his requests for a downward departure or variance.
Finally, Robinson asserts the district court should not have afforded deference to the
pornography Guidelines. The argument that a district court errs by refusing to
disregard the pornography Guidelines on empirical grounds is not properly before us.
See, e.g., United States v. Muhlenbruch, 

, 1102 (8th Cir. 2012). Our
review is "'limited to determining the substantive reasonableness of a specific sentence
where the advisory guidelines range was determined' in accordance with the
guidelines." United States v. Pappas, 

, 229 (8th Cir. 2013) (quoting
United States v. Shuler, 

, 448 (8th Cir. 2010)).

      Accordingly, we affirm. See 8th Cir. R. 47B.
                     ______________________________


      1
       The Honorable Linda R. Reade, Chief, Judge, United States District Court for
the Northern District of Iowa.

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