x1 := (1,2,4,7)(3,5,9,14)(6,10,16,24)(8,12,19,28)(11,17,26,18)(13,20,30,42)
     (15,22,33,44)(21,31,35,32)(23,34,46,60)(25,36,47,62)(27,38,50,67)(29,40,
     53,71)(37,48,64,82)(39,51,69,52)(41,54,73,92)(43,56,66,84)(45,58,77,98)
     (49,65,83,105)(55,74,94,61)(57,75,96,76)(59,78)(63,80,102,127)(68,86,108,
     133)(70,88,111,138)(72,90,114,142)(79,100,125,101)(81,103,91,115)(85,99,
     123,107)(87,109,135,167)(89,112,140,113)(93,117,146,178)(95,119,149,180)
     (97,121,152,185)(104,129,160,194)(106,131,163,148)(110,136,168,204)(116,
     144,177,145)(118,147,143,175)(120,150,182,218)(122,153,187,154)(124,155,
     174,211)(126,157,190,227)(128,159,137,169)(130,161,196,162)(132,164,199,
     235)(134,166,202,239)(139,171,207,242)(141,173,210,247)(151,183,219,256)
     (156,188,217,254)(158,191,229,192)(165,200,237,201)(170,206)(172,208,244,
     285)(176,205,241,281)(179,214,252,294)(181,216,215,253)(184,220,258,297)
     (186,222,261,278)(189,225,264,305)(193,213,250,291)(195,231,270,312)(197,
     233,273,315)(198,223,262,301)(203,212,249,290)(209,245,286,330)(221,259,
     299,260)(224,263,303,342)(226,265,307,351)(228,267,310,354)(230,268,257,
     269)(232,271,313,357)(234,274,284,328)(236,276,319,320)(238,277,321,300)
     (240,279,323,280)(243,283,327,370)(246,287,332,375)(248,289,335,302)(251,
     292,338,373)(255,296,343,384)(266,308,352,309)(272,314,358,400)(275,317,
     361,318)(282,325,368,326)(288,333,377,334)(293,339,347,389)(295,341,382,
     304)(298,345,387,423)(306,350,393,432)(311,355,331,374)(316,359,329,372)
     (322,364,405,443)(324,366,404,336)(337,379,415,397)(340,380,417,381)(344,
     385,378,386)(346,388,425,414)(348,390,428,460)(349,391,430,392)(353,395,
     434,465)(356,398,437,394)(360,401,402,441)(362,403,422,413)(363,376,412,
     450)(365,406,445,411)(367,396,435,466)(369,408,399,438)(371,410,442,440)
     (383,419,454,479)(407,446,470,494)(409,448,473,449)(416,451,436,420)(418,
     453,477,485)(421,439,467,427)(424,456,452,475)(426,458,483,474)(429,461,
     486,501)(431,463,489,472)(433,464,490,444)(447,471,495,509)(455,480,476,
     481)(457,482,478,491)(459,484,499,469)(462,487,502,512)(468,493,508,507)
     (488,503,513,500)(492,506,511,515)(496,504)(497,505)(498,510,516,519)
     (514,518,517,520);