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%I #13 Jan 15 2021 16:31:19
%S 1,1,2,6,1,8,3,1,11,7,4,3,2,2,2,2,2,2,3,4,5,7,11,1,1,3,5,9,1,2,4,9,1,
%T 3,6,1,2,6,1,2,7,1,3,10,2,6,1,4,12,2,9,2,7,1,6,1,5,1,5,1,5,1,6,1,7,2,
%U 10,2,13,4,1,6,1,9,3,1,5,1,9,3,1,6,2,12,4,1,10,3,1,9,3,1,9,3,1,10,4,1,12,5
%N a(n) = leading digit of n! in base 15.
%H David A. Corneth, <a href="/A136765/b136765.txt">Table of n, a(n) for n = 0..9999</a>
%e a(10) = 4 as 10! = 41110300_15 which has leading digit 4. - _David A. Corneth_, Jan 15 2021
%t f[n_]:=First[IntegerDigits[n!,15]]; lst={};Do[AppendTo[lst,f[n]],{n,0,2*5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 14 2009 *)
%o (PARI) a(n) = digits(n!, 15)[1]; \\ _Michel Marcus_, Jan 27 2015
%Y Cf. A000142, A136701, A136754, A136755, A136756, A136757, A136758, A136759, A136760, A008905, A136761, A136762, A136763, A136764, A136766.
%K nonn,easy,base
%O 0,3
%A _Carl R. White_, Jan 21 2008