z1 := (1,2)(3,5)(4,7)(6,8)(9,13)(10,15)(11,16)(12,18)(14,21)(17,26)(19,29)(22,
     31)(23,33)(24,34)(25,36)(28,38)(30,41)(32,44)(35,49)(37,52)(39,55)(40,57)
     (42,59)(43,61)(45,63)(46,47)(48,66)(50,68)(51,70)(53,72)(54,74)(56,77)
     (58,80)(60,82)(62,85)(64,88)(65,89)(67,90)(69,91)(71,93)(73,96)(75,99)
     (76,101)(79,105)(81,108)(84,111)(86,112)(92,121)(94,122)(97,126)(98,128)
     (100,131)(102,133)(103,135)(104,109)(106,138)(107,118)(110,137)(113,144)
     (114,146)(115,147)(116,149)(117,150)(119,151)(120,123)(124,154)(125,156)
     (127,158)(129,160)(130,162)(132,165)(136,170)(140,174)(141,175)(142,176)
     (143,177)(145,180)(148,183)(152,189)(153,190)(157,193)(159,196)(161,198)
     (163,201)(164,194)(166,204)(167,205)(168,203)(169,207)(171,208)(172,209)
     (173,210)(178,212)(179,184)(181,214)(182,215)(185,217)(186,206)(187,213)
     (188,219)(191,220)(192,221)(195,218)(197,225)(199,227)(200,229)(202,230)
     (222,241)(223,242)(224,244)(226,246)(228,249)(231,254)(232,255)(233,256)
     (234,258)(235,259)(236,260)(237,261)(238,262)(239,264)(240,265)(243,270)
     (245,273)(247,274)(248,276)(251,280)(252,281)(253,282)(266,285)(267,287)
     (268,288)(271,283)(272,278)(275,290)(277,291)(279,286)(284,289)(292,294)
     (293,296)(295,297);