A078670 Number of times n appears among the decimal digits of (n!)!.

1, 1, 0, 4, 21, 169, 1504, 15755, 177333, 213789

Offset: 1

Author

Jason Earls, Dec 16 2002

Keywords

• base
• more
• nonn

Examples

			a(4)=4 because 4 appears four times in (4!)! = 620448401733239439360000.
		

Crossrefs

Cf. A000197.

Programs

Mathematica

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 *)

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!!)","))

Extensions

Added a(9) and a(10). - Ryan Leonel (ryan.leonel(AT)gmail.com), Oct 03 2008