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A078264
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Integer part of the geometric mean of the forward and reverse concatenations of 1 to n.
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1
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1, 15, 198, 2309, 25895, 284217, 3074048, 32896079, 349188532, 11646890238, 1171148874112, 122278263238675, 12727490844526758, 1320830780128673820, 136722265049041488664, 14120912163801368446154
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(3) =123*321 = 39483.
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PROG
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(PARI) f="1"; b="1"; for(i=2, 40, print1(sqrtint(eval(f)*eval(b)), ", "); f=concat(f, Str(i)); b=concat(Str(i), b)) - Lambert Herrgesell (zero815(AT)googlemail.com), Mar 13 2006
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Mar 13 2006
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STATUS
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approved
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