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A004153
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Factorial numbers written backwards.
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4
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1, 1, 2, 6, 42, 21, 27, 405, 2304, 88263, 88263, 861993, 6100974, 80207226, 219287178, 8634767031, 88898722902, 690824786553, 8275073732046, 238804001546121, 466718002092342, 4490717124909015, 867067777270004211, 4667948883761025852, 63934932337104844026
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refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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LINKS
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FORMULA
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MAPLE
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a:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||(n!)):
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PROG
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(PARI) reverse(expr)=my(v=Vec(Str(expr)), n=length(v)); eval(concat(vector(n, i, v[n-i+1])));
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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