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<p>Create Project Euler/230 - Fibonacci Words (via create-page on MediaWiki MCP Server)</p> <p><b>New page</b></p><div>==Problem Statement==<br /> <br /> &#039;&#039;&#039;Fibonacci Words&#039;&#039;&#039;<br /> <br /> For any two strings of digits, A and B, we define F_{A,B} to be the sequence (A, B, AB, BAB, ABBAB, ...) in which each term is the concatenation of the previous two.<br /> <br /> Further, we define D_{A,B}(n) to be the nth digit in the first term of F_{A,B} that contains at least n digits.<br /> <br /> Example:<br /> Let A=1415926535, B=8979323846. We wish to find D_{A,B}(35), say.<br /> The first few terms of F_{A,B} are:<br /> 1415926535<br /> 8979323846<br /> 14159265358979323846<br /> 897932384614159265358979323846<br /> 14159265358979323846897932384614159265358979323846<br /> <br /> Then D_{A,B}(35) is the 35th digit in the fifth term, which is 9.<br /> <br /> Now we use for A the first 100 digits of π behind the decimal point:<br /> 14159265358979323846264338327950288419716939937510<br /> 58209749445923078164062862089986280348253421170679<br /> <br /> and for B the next hundred digits:<br /> 82148086513282306647093844609550582231725359408128<br /> 48111745028410270193852110555964462294895493038196 .<br /> <br /> Find ∑_{n = 0,1,...,17} 10^n × D_{A,B}((127+19n)×7^n).<br /> <br /> ==Flags==<br /> <br /> {{ProjectEulerFlag}}</div>

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