a21 := (1,2,4,6,10)(3,5,8,13,19)(7,11,17,24,36)(9,14,20,29,41)(12,18,26,38,52)
     (15,21,31,44,59)(16,22,33,46,63)(23,34,48,66,91)(25,37,51,71,97)(27,39,
     53,73,100)(28,40,54,75,103)(30,42,56,78,106)(32,45,61,84,113)(35,49,68,
     93,126)(43,57,80,108,142)(47,64,88,118,156)(50,69,94,127,164)(55,76,104,
     137,176)(58,81,110,145,185)(60,82,111,147,188)(62,85,115,152,193)(65,89,
     120,158,201)(67,92,124,162,206)(70,95,128,165,208)(72,98,130,168,212)(74,
     101,134,173,218)(77,105,139,179,224)(79,107,141,182,227)(83,112,149,191,
     236)(86,116,153,194,241)(87,117,155,197,245)(90,121,159,202,249)(96,129,
     166,209,256)(99,131,169,213,190)(102,135,174,219,123)(109,143,183,229,
     276)(114,150,192,238,286)(119,157,199,140,180)(122,160,203,251,300)(125,
     163,207,254,151)(132,170,214,260,308)(133,171,215,262,310)(136,175,220,
     266,315)(138,177,222,269,319)(144,184,231,279,330)(146,186,233,281,332)
     (148,189,235,284,335)(154,195,243,290,342)(161,204,239,287,338)(167,210,
     257,304,357)(172,216,263,311,364)(178,205,253,302,354)(181,225,272,322,
     373)(187,234,255,303,355)(196,244,292,345,394)(200,246,294,347,387)(211,
     258,305,359,405)(217,264,312,365,411)(221,267,316,369,417)(223,270,320,
     314,367)(226,273,323,375,423)(228,274,325,377,400)(230,277,328,381,352)
     (232,280,331,382,428)(237,285,336,386,434)(240,288,339,388,297)(242,289,
     341,391,435)(247,295,348,397,442)(248,296,349,282,333)(250,298,350,399,
     444)(252,301,353,402,414)(259,306,360,406,450)(261,309,362,409,453)(265,
     313,366,413,457)(268,317,370,363,410)(271,321,372,420,463)(275,326,379,
     416,458)(278,329,368,415,431)(283,334,385,432,472)(291,343,392,436,475)
     (293,346,395,440,479)(299,351,401,445,483)(307,361,408,439,478)(318,371,
     418,460,491)(324,376,425,467,496)(327,380,427,356,403)(340,389,424,422,
     448)(344,393,433,473,503)(358,404,447,485,378)(374,421,465,494,484)(383,
     429,469,498,482)(384,430,470,499,513)(390,426,459,490,511)(396,441,462,
     474,504)(398,443,481,506,449)(407,451,486,507,516)(412,455,487,508,510)
     (419,461,492,480,456)(437,476,505,468,497)(438,477,454,488,502)(446,471,
     500,514,452)(464,493,512,518,523)(466,495,501,515,519)(489,509,517,521,
     524)(520,522,525,526,528);