n30 15,16,17; 18,19,20; 21,22,23; 15,18,21; 15,24,25; 18,26,27; 21,28,29; 16,19,22; 16,26,28; 19,24,29; 22,25,27; 17,20,23; 17,27,29; 20,25,28; 23,24,26; 0,3,4; 0,7,8; 0,11,12; 1,3,5; 1,7,9; 1,11,13; 2,3,6; 2,7,10; 2,11,14; 4,9,14; 4,10,13; 5,8,14; 5,10,12; 6,8,13; 6,9,12.