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Omit 5's from n.
4

%I #18 Jan 14 2020 05:32:35

%S 0,1,2,3,4,0,6,7,8,9,10,11,12,13,14,1,16,17,18,19,20,21,22,23,24,2,26,

%T 27,28,29,30,31,32,33,34,3,36,37,38,39,40,41,42,43,44,4,46,47,48,49,0,

%U 1,2,3,4,0,6,7,8,9,60,61,62,63,64,6,66,67,68,69,70,71,72,73,74

%N Omit 5's from n.

%C See A004724 for a variant where a(n) disappears when n has only digits 5. - _M. F. Hasler_, Jan 13 2020

%t Table[FromDigits[DeleteCases[IntegerDigits[n], 5]], {n, 0, 79}] (* _Harvey P. Dale_, Jan 20 2015 *)

%o (PARI) a(n)=subst(Pol(select(k->k-5,digits(n))),'x,10) \\ _Charles R Greathouse IV_, Oct 16 2012

%o (PARI) A004180(n)=fromdigits([d|d<-digits(n),d!=5]) \\ _M. F. Hasler_, Jan 13 2020

%o (Scala) (0 to 99).map(n => try {

%o Integer.parseInt(Integer.toString(n).replace("5", ""))

%o } catch {

%o case _: NumberFormatException => 0

%o }) // _Alonso del Arte_, Jan 13 2020

%o (MATLAB) for u=0:74 ; v=dec2base(u, 10)-'0'; v = v(v~=5); if length(v)>0; sol(u+1)=(str2num(strrep(num2str(v), ' ', ''))); else; sol(u+1)=0; end; end; sol % _Marius A. Burtea_, Jan 13 2020

%Y Cf. A004724.

%K nonn,base,easy

%O 0,3

%A _N. J. A. Sloane_