BBasis[20,{20}] =
{Graph[C1[41], C1[42], C1[43], C1[45], C1[44], C1[47], C1[46], C1[49], 
   C1[48], C1[51], C1[50], C1[53], C1[52], C1[55], C1[54], C1[57], C1[56], 
   C1[60], C1[59], C1[58], Dashed[41, 43], Dashed[41, 42], Dashed[43, 45], 
   Dashed[42, 44], Dashed[45, 47], Dashed[44, 46], Dashed[47, 49], 
   Dashed[46, 48], Dashed[49, 51], Dashed[48, 50], Dashed[51, 53], 
   Dashed[50, 52], Dashed[53, 55], Dashed[52, 54], Dashed[55, 57], 
   Dashed[54, 56], Dashed[57, 59], Dashed[56, 58], Dashed[59, 60], 
   Dashed[58, 60], OV[1, 21, 22], OV[2, 22, 24], OV[3, 21, 23], 
   OV[5, 24, 26], OV[4, 23, 25], OV[7, 26, 28], OV[6, 25, 27], OV[9, 28, 30], 
   OV[8, 27, 29], OV[11, 30, 32], OV[10, 29, 31], OV[13, 32, 34], 
   OV[12, 31, 33], OV[15, 34, 36], OV[14, 33, 35], OV[17, 36, 38], 
   OV[16, 35, 37], OV[20, 38, 40], OV[19, 37, 39], OV[18, 39, 40]]}