. Appellant contends that Skinner v. Oklahoma ex rel. Williamson, 316 U.S. 535, 62 S.Ct. 1110, 86 L.Ed. 1655 (1942), announces his right to receive a- sentence similar to that of his co-defendant. Skinner, however, concerned the arbitrary legislative classification of individuals, whereas no such classification appears in the instant case. Appellant further argues that the failure of the judge to delineate reasons for petitioner’s sentence causes a “chilling effect” on a defendant’s exercise of his constitutional rights. Dombrowski v. Pfister, 380 U.S. 479, 85 S.Ct. 1116, 14 L.Ed.2d 22 (1965). There is no evidence, however, to support the argument that appellant was given a lengthier sentence because he chose to assert his guaranteed rights. Indeed, when the First Circuit was faced with this precise contention, it noted that “[i]t is too frivolous to merit discussion.” Green v. United States, 334 F.2d 733, 736 (1st Cir. 1964). Appellant’s reference in a supplemental letter filed with this court to Prince v. United States, 352 U.S. 322, 77 S.Ct. 403, 1 L.Ed.2d 370 (1957), and Heflin v. United States, 358 U.S. 415, 79 S.Ct. 451, 3 L.Ed.2d 407 (1959) is misplaced. Prince held that the crime of entry into a bank with intent to rob was not intended by Congress to be a separate offense from the consummated robbery, whereas Heflin held only that subsection (c) of § 2113 was intended “only to provide punishment for those who receive the loot” from the actual bank robbers.