b21 := (2,3,4)(5,7,8)(6,9,10)(11,15,14)(12,16,17)(13,18,19)(20,25,26)(21,27,24)
     (22,28,29)(23,30,31)(32,39,40)(33,41,42)(34,43,44)(35,45,46)(36,47,48)
     (37,49,50)(38,51,52)(53,67,56)(54,65,68)(55,69,60)(57,70,71)(58,72,73)
     (59,74,75)(61,76,77)(62,78,79)(63,80,81)(64,82,83)(66,84,85)(86,104,105)
     (87,106,107)(88,108,91)(89,100,109)(90,110,95)(92,111,112)(93,113,114)
     (94,115,116)(96,117,118)(97,119,120)(98,121,122)(99,123,124)(101,125,126)
     (102,127,128)(103,129,130)(131,153,154)(132,155,156)(133,157,158)(134,
     159,160)(135,161,152)(136,162,163)(137,164,142)(138,149,165)(139,166,167)
     (140,168,169)(141,170,171)(143,172,173)(144,174,175)(145,176,150)(146,
     177,178)(147,179,180)(148,181,182)(151,183,184)(185,205,204)(186,206,207)
     (187,208,209)(188,191,210)(189,211,212)(190,213,214)(192,215,216)(193,
     217,218)(194,219,220)(195,221,222)(196,223,224)(199,225,226)(200,227,228)
     (201,229,230)(202,231,232)(203,233,234);