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A038524
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Numbers k such that the k-th Fibonacci number is composite and the concatenation of its prime factors (written in base 10 in ascending order) is prime.
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0
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8, 24, 28, 34, 50, 52, 58, 71, 77, 163, 197, 235, 238, 319, 570, 669, 949, 958, 1211, 1305
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OFFSET
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1,1
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LINKS
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EXAMPLE
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F(24) = 46368 = 2^5 * 3^2 * 7 * 23 is composite and the concatenation 2222233723 is prime, so 24 is in the sequence.
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CROSSREFS
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KEYWORD
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nonn,base,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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