00409nam a2200181Ia 4500003000400000005001700004008004100021020001900062040000700081041000800088082001500096100002200111245003100133260002000164300000800184650001600192700001900208OSt20251219111126.0250729s2003 xx 000 0 und d a978-8172452926 cAL aeng a510.2 NIEH aNiederman Derrick aHard-to-solve math puzzles aNew Delhic2003 a92p aMathematics aRao Digumurthi