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A078670
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Number of times n appears among the decimal digits of (n!)!.
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0
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OFFSET
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1,4
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LINKS
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EXAMPLE
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a(4)=4 because 4 appears four times in (4!)! = 620448401733239439360000.
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MATHEMATICA
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Table[Count[Partition[IntegerDigits[(n!)!], IntegerLength[n], 1], IntegerDigits[ n]], {n, 10}] (* Harvey P. Dale, May 19 2014 *)
Table[SequenceCount[IntegerDigits[(n!)!], IntegerDigits[n]], {n, 10}] (* The program uses the SequenceCount function from Mathematica version 10 *) (* Harvey P. Dale, Aug 08 2016 *)
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PROG
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(PARI) {mdcp(d, n)=local(a, c=0, L); L=length(Str(d)); if(L>1, a=2, a=1); while(n>0, if(n%(10^a)==d, n=floor(n/10); c++, n=floor(n/10); )); c } for(n=1, 10, print1(mdcp(n, n!!)", "))
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CROSSREFS
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KEYWORD
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base,more,nonn
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AUTHOR
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EXTENSIONS
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Added a(9) and a(10). - Ryan Leonel (ryan.leonel(AT)gmail.com), Oct 03 2008
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STATUS
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approved
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