1. Preve that the center entry at a 3 x 3 traditional magic square must he 5. 2. [BeekHehins, #615] Recall that Hn] is the number of n. :u: n semimagic squares with line sume t, and Hlt] is the number Inf :1 :u: n semimagic squares with line sum t having all entries strictly pcsitive. Prcve that far all t 33 n, Ht] = Hn n}. 3. [BeckEchins, #63] Preve that H:<1J=s<2)=m=s{nn=n. ti. Use inductinn tn prmre that the Eirkhn' pelepe B\" has the integer decampesiiien pmperty: for every lattice point i: E t3\" I"'I 3"\