b21 := (1,3,6)(2,4,8)(5,9,14)(7,11,16)(10,15,21)(12,17,24)(13,18,26)(19,27,36) (20,28,38)(22,30,41)(23,31,43)(25,33,46)(29,39,53)(32,44,59)(34,47,63) (35,48,65)(37,50,67)(40,54,72)(42,56,75)(45,60,80)(51,68,89)(52,69,91) (55,73,95)(57,76,99)(58,77,101)(61,81,106)(62,82,108)(64,84,111)(66,86, 114)(70,92,121)(71,85,112)(74,96,126)(78,102,133)(79,103,135)(83,109,142) (87,115,149)(88,116,151)(90,118,154)(93,122,159)(94,123,161)(97,127,166) (98,128,168)(100,130,171)(104,136,177)(105,137,179)(107,139,182)(110,143, 187)(113,146,191)(117,152,197)(119,155,201)(120,156,203)(124,162,209) (125,163,211)(129,169,217)(131,172,221)(132,173,223)(134,175,226)(138, 180,232)(140,183,236)(141,184,238)(144,188,242)(145,189,244)(147,192,248) (148,193,250)(150,195,253)(153,198,257)(157,204,263)(158,205,265)(160, 207,268)(164,212,273)(165,213,274)(167,215,276)(170,218,280)(174,224,286) (176,227,290)(178,229,293)(181,233,298)(185,239,304)(186,240,306)(190, 245,311)(194,251,317)(196,254,321)(199,258,325)(200,259,327)(202,260,329) (206,266,333)(208,269,337)(210,271,340)(214,275,345)(216,277,348)(219, 281,353)(220,282,355)(222,284,358)(225,287,362)(228,291,366)(230,294,369) (231,295,371)(234,299,376)(235,300,378)(237,302,381)(241,307,386)(243, 309,389)(246,312,392)(247,313,394)(249,315,397)(252,318,401)(255,267,334) (256,322,303)(261,314,395)(262,330,411)(264,331,413)(270,338,421)(272, 341,425)(278,349,433)(279,350,435)(283,356,442)(285,359,444)(288,363,449) (289,364,451)(292,367,454)(296,372,459)(297,373,461)(301,379,467)(305, 383,472)(308,387,476)(310,390,479)(316,398,488)(319,402,478)(320,344,428) (323,404,493)(324,405,495)(326,406,497)(328,408,499)(332,414,465)(335, 417,508)(336,418,510)(339,422,514)(342,426,518)(343,427,520)(346,430,522) (347,431,524)(351,436,529)(352,437,531)(354,439,534)(360,445,539)(361, 446,541)(365,452,548)(368,455,552)(370,457,555)(374,462,407)(375,463,560) (377,410,501)(380,468,564)(382,470,567)(384,473,571)(385,474,573)(388, 477,577)(391,480,580)(393,482,583)(396,485,559)(399,489,591)(400,490,566) (403,492,594)(409,500,601)(412,503,603)(415,505,605)(416,506,607)(419, 511,613)(420,429,519)(423,491,592)(424,515,618)(432,525,625)(434,526,627) (438,532,633)(440,535,611)(441,536,638)(443,537,640)(447,542,646)(448, 543,648)(450,545,650)(453,549,655)(456,553,660)(458,556,663)(460,558,666) (464,561,621)(466,562,670)(469,565,674)(471,568,677)(475,574,682)(481, 581,687)(483,584,590)(484,585,690)(486,587,693)(487,588,695)(494,582,688) (496,596,701)(498,598,703)(502,547,652)(504,546,651)(507,608,712)(509, 610,715)(512,614,718)(513,615,673)(516,619,723)(517,620,725)(521,622,668) (523,623,727)(527,628,733)(528,629,735)(530,631,736)(533,634,740)(538, 641,745)(540,643,748)(544,649,753)(550,656,760)(551,657,762)(554,661,767) (557,664,771)(563,671,575)(569,678,780)(570,679,672)(572,680,781)(576, 683,784)(578,684,786)(579,685,788)(586,691,636)(589,696,697)(593,699,630) (595,700,799)(597,702,802)(599,704,804)(600,705,806)(602,706,689)(604, 708,809)(606,710,812)(609,713,815)(612,716,785)(616,720,823)(617,721,635) (624,728,829)(626,730,832)(632,737,840)(637,741,845)(639,743,825)(642, 746,779)(644,749,851)(645,750,853)(647,752,855)(653,757,861)(654,758,863) (658,763,868)(659,764,870)(662,768,874)(665,772,878)(667,774,879)(669, 775,769)(675,777,882)(676,778,884)(681,782,888)(686,789,800)(692,793,896) (694,794,897)(698,797,900)(707,742,787)(709,810,908)(711,813,911)(714, 816,914)(717,819,744)(719,821,916)(722,824,919)(724,826,828)(726,734,836) (729,830,923)(731,833,927)(732,834,929)(738,841,935)(739,842,936)(747, 848,867)(754,857,950)(755,858,952)(756,859,953)(759,864,957)(761,866,959) (765,871,964)(766,872,965)(770,875,969)(773,844,938)(776,827,921)(783, 889,979)(790,893,865)(791,894,986)(792,895,988)(795,898,990)(796,899,991) (798,901,993)(801,891,982)(803,846,939)(805,903,941)(807,905,817)(808, 906,820)(811,909,818)(814,912,1001)(822,917,837)(831,924,1011)(835,930, 1018)(838,931,1019)(839,932,1021)(843,937,1027)(847,940,1031)(849,942, 1033)(850,943,1035)(852,945,1038)(854,947,1041)(856,949,1043)(860,954, 1049)(862,955,1051)(869,961,1056)(873,966,1062)(876,970,1067)(877,971, 1069)(880,973,1072)(881,974,1074)(883,918,1005)(885,976,1076)(886,977, 1046)(887,978,1078)(890,981,1079)(892,983,995)(902,994,1087)(904,975, 1075)(907,997,915)(910,999,1089)(913,1002,1032)(920,1007,1095)(922,1008, 1097)(925,1012,1101)(926,1013,1103)(928,1015,1105)(933,1022,1110)(934, 1023,1112)(944,1036,1121)(946,1039,1123)(948,1042,1125)(951,1045,960) (956,1052,1133)(958,1054,1135)(962,1057,996)(963,1058,1139)(967,1063, 1145)(968,1064,1147)(972,1070,1153)(984,1080,1156)(985,1081,1158)(987, 992,1085)(989,1082,1160)(998,1088,1165)(1000,1083,1161)(1003,1091,1009) (1004,1092,1116)(1006,1093,1169)(1010,1098,1173)(1014,1104,1178)(1016, 1106,1181)(1017,1107,1182)(1020,1109,1184)(1024,1113,1132)(1025,1114, 1177)(1026,1115,1187)(1028,1071,1094)(1029,1061,1142)(1030,1117,1183) (1034,1119,1053)(1037,1122,1180)(1040,1124,1157)(1044,1127,1196)(1047, 1129,1197)(1048,1130,1198)(1050,1126,1194)(1055,1136,1204)(1059,1140, 1207)(1060,1141,1209)(1065,1148,1214)(1066,1149,1216)(1068,1151,1219) (1073,1154,1168)(1086,1163,1224)(1090,1166,1215)(1096,1170,1208)(1099, 1174,1108)(1100,1144,1118)(1102,1176,1202)(1111,1185,1128)(1120,1190, 1239)(1131,1199,1192)(1134,1201,1246)(1137,1205,1218)(1138,1164,1225) (1143,1162,1223)(1150,1217,1226)(1152,1220,1254)(1155,1188,1193)(1159, 1175,1233)(1167,1228,1257)(1171,1229,1259)(1172,1230,1213)(1179,1232, 1261)(1186,1203,1242)(1189,1237,1238)(1191,1235,1263)(1195,1240,1265) (1200,1244,1258)(1206,1247,1269)(1210,1222,1221)(1211,1250,1241)(1212, 1251,1271)(1227,1255,1273)(1231,1260,1264)(1236,1249,1252)(1243,1266, 1278)(1245,1267,1279)(1248,1270,1280)(1253,1272,1268)(1256,1274,1275) (1262,1276,1281)(1277,1282,1284)(1283,1286,1288);