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%I #2 Oct 02 2013 15:12:48
%S 1,26,227,1629,49517,125488,125488
%N Indices of Fibonacci numbers in A068136(n); that is, a(n) = least k such that the digits of Fibonacci(k) begin with the concatenation 1234..n.
%C The sequence is strictly nondecreasing. Next term, if it exists, is greater than 1,800,000.
%e fibonacci(227) = 123227981463641240980692501505442003148737643593 is the least Fibonacci number beginning with the concatenation 123, so a(3) = 227.
%t k = 1; Do[l = IntegerDigits[Fibonacci[n]]; While[Take[l, Min[Length[l], k]] == Range[1, k], Print[n]; k++ ], {n, 1, 1800000}]
%Y Cf. A068136 (corresponding Fibonacci numbers).
%K base,hard,nonn
%O 1,2
%A _Ryan Propper_, Sep 10 2005