Weird behavior when randomizing dynamic array

In reply to eda2k4:

Without extra constraint, I get the following:
burst_len[0] = 1584258998
burst_len[1] = 3134088755
burst_len[2] = 828825450
burst_len[3] = 4111691712
burst_len[4] = 1968018003
burst_len[5] = 824687916
burst_len[6] = 1008475836
burst_len[7] = 1491683716
burst_len[8] = 1319840510
burst_len[9] = 908298388

With extra (and unnecessary IMO) constraint, I get the right result:
burst_len[0] = 5
burst_len[1] = 3
burst_len[2] = 16
burst_len[3] = 39
burst_len[4] = 2
burst_len[5] = 3
burst_len[6] = 2
burst_len[7] = 26
burst_len[8] = 2
burst_len[9] = 2