[oyesikwk] bpm seconds

conversion table between beats per minute (music) and interval between beats in seconds (inspired by the -d argument to 'top'):

30 2.00
35 1.71
40 1.50
45 1.33
50 1.20
55 1.09
60 1.00
65 0.92
70 0.86
75 0.80
77.46 0.7746 (10^n * sqrt 60)
80 0.75
85 0.71
90 0.67
95 0.63
100 0.60
105 0.57
110 0.55
115 0.52
120 0.50
130 0.46
140 0.43
150 0.40
160 0.38
170 0.35
180 0.33
190 0.32
200 0.30
210 0.29
220 0.27
230 0.26
240 0.25
244.94897 0.24494897 (10^n * sqrt 6)
250 0.24
260 0.23
270 0.22
280 0.21
285.7142857 0.210000
290 0.21
300 0.20