A004179 Omit 4's from n.

0, 1, 2, 3, 0, 5, 6, 7, 8, 9, 10, 11, 12, 13, 1, 15, 16, 17, 18, 19, 20, 21, 22, 23, 2, 25, 26, 27, 28, 29, 30, 31, 32, 33, 3, 35, 36, 37, 38, 39, 0, 1, 2, 3, 0, 5, 6, 7, 8, 9, 50, 51, 52, 53, 5, 55, 56, 57, 58, 59, 60, 61, 62, 63, 6, 65, 66, 67, 68, 69, 70, 71, 72, 73, 7

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• base
• easy

Links

• Marius A. Burtea, Table of n, a(n) for n = 0..10000

Programs

MATLAB

for u=0:100 ;v=dec2base(u, 10)-'0';v = v(v~=4);
  if length(v)>0; sol(u+1)=(str2num(strrep(num2str(v), ' ', '')));else; sol(u+1)=0; end; end;
sol % Marius A. Burtea, May 20 2019

Mathematica

Table[FromDigits[DeleteCases[IntegerDigits[n], 4]], {n, 0, 100}] (* Vincenzo Librandi, May 22 2019 *)

PARI

a(n)=subst(Pol(select(k->k-4,digits(n))),'x,10) \\ Charles R Greathouse IV, Oct 16 2012