One-Sixtieth
דברים כו, ב : וְלָקַחְתָ מֵרֵאשִׁית כָל-פְרִׁ י הָאֲדָמָה אֲשֶׁר תָבִׁיא מֵאַרְ צְךָ אֲשֶׁר ה' אֱלֹקֶׁיךָ נֹתֵן לָךְ וְשַמְתָ בַטֶׁנֶׁא
Baal HaTurim notes that the Gematria of the word טנא is 60. The Rambam in hilchos Bikurim 2:15 writes that the Torah does not specify the amount required to be given for Bikurim. However, the Rabbis required a person to give 1/60th. For this reason the letter ס is absent from this passage about Bikurim.
Perhaps his intention is that since one is required by Rabbinical decree to give a sixtieth; the owner will be left with 59 parts, with one going to the Kohen, which is alluded in the word טנ( 59)א(1). Therefore we don't have the letter that equals 60 in this chapter. Also, the Torah uses the unusual word טנא (which appears 4 times in Tanach) and not the usual word סל (which appears 15 times in Tanach) for a basket.
