n = 51; f = 1/20*[-59.1511 -56.1064 -50.2748 -49.4777 -37.8666 -39.1663 -29.5690 -23.1988 -13.5347 -19.0507 -13.5943 -3.3281 4.3185 -0.8454 -5.2978 -4.2539 -4.8049 3.4295 -7.6252 -2.9975 -7.9095 -10.6627 -3.6029 2.1732 -8.9521 -3.4540 3.6084 9.1472 3.9546 6.3898 13.0362 2.7332 13.4027 10.6478 0.9049 5.0750 6.0504 -0.6255 0.9780 -2.9543 -2.8318 -1.5979 -3.5722 1.1280 8.8262 18.4649 15.2587 30.3260 23.3266 34.6998 28.5653];