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

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

Offset

1,4

Links

Table of n, a(n) for n=1..10.

Example

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

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 *)

Prog

(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!!)", "))

Crossrefs

Cf. A000197.

Sequence in context: A107872 A008858 A217484 * A317104 A163948 A278993

Adjacent sequences: A078667 A078668 A078669 * A078671 A078672 A078673

Keyword

base,more,nonn

Author

Jason Earls, Dec 16 2002

Extensions

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

Status

approved