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A110486
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.
1
1, 26, 227, 1629, 49517, 125488, 125488
OFFSET
1,2
COMMENTS
The sequence is strictly nondecreasing. Next term, if it exists, is greater than 1,800,000.
EXAMPLE
fibonacci(227) = 123227981463641240980692501505442003148737643593 is the least Fibonacci number beginning with the concatenation 123, so a(3) = 227.
MATHEMATICA
k = 1; Do[l = IntegerDigits[Fibonacci[n]]; While[Take[l, Min[Length[l], k]] == Range[1, k], Print[n]; k++ ], {n, 1, 1800000}]
CROSSREFS
Cf. A068136 (corresponding Fibonacci numbers).
Sequence in context: A269658 A220714 A159519 * A098994 A172124 A196633
KEYWORD
base,hard,nonn
AUTHOR
Ryan Propper, Sep 10 2005
STATUS
approved