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#!/usr/bin/awk -f ### fib.awk # fib sol'n from Hamming BEGIN { ARGV[1] ? n = ARGV[1] : n = 0 ARGV[2] ? OFMT = "%." ARGV[2] "g" : OFMT = "%g" C1 = 1.0/sqrt(5) C2 = -1.0/sqrt(5) print C1*(0.5*(1 + sqrt(5)))^n + C2*(0.5*(1 - sqrt(5)))^n }