cp's OEIS Frontend

A064532 Total number of holes in decimal expansion of the number n, assuming 4 has no hole.

%I A064532 #21 Nov 18 2022 18:09:03
%S A064532 1,0,0,0,0,0,1,0,2,1,1,0,0,0,0,0,1,0,2,1,1,0,0,0,0,0,1,0,2,1,1,0,0,0,
%T A064532 0,0,1,0,2,1,1,0,0,0,0,0,1,0,2,1,1,0,0,0,0,0,1,0,2,1,2,1,1,1,1,1,2,1,
%U A064532 3,2,1,0,0,0,0,0,1,0,2,1,3,2,2,2,2,2,3,2,4,3,2,1,1,1,1,1,2,1,3,2,2,1,1,1,1
%N A064532 Total number of holes in decimal expansion of the number n, assuming 4 has no hole.
%C A064532 Assumes that 4 is represented without a hole.
%H A064532 Indranil Ghosh, <a href="/A064532/b064532.txt">Table of n, a(n) for n = 0..50000</a>
%F A064532 a(10i+j) = a(i) + a(j), etc.
%e A064532 8 has two holes so a(8) = 2.
%t A064532 a[n_ /; 0 <= n <= 9] := a[n] = {1, 0, 0, 0, 0, 0, 1, 0, 2, 1}[[n + 1]]; a[n_] := Total[a[#] + 1 &  /@ (id = IntegerDigits[n])] - Length[id];  Table[a[n], {n, 0, 104}] (* _Jean-François Alcover_, Nov 22 2013 *)
%t A064532 Table[DigitCount[x].{0, 0, 0, 0, 0, 1, 0, 2, 1, 1}, {x, 0, 104}] (* _Michael De Vlieger_, Feb 02 2017, after _Zak Seidov_ at A064692 *)
%o A064532 (Python)
%o A064532 def A064532(n):
%o A064532     x=str(n)
%o A064532     return x.count("0")+x.count("6")+x.count("8")*2+x.count("9") # _Indranil Ghosh_, Feb 02 2017
%o A064532 (PARI) h(n) = [1, 0, 0, 0, 0, 0, 1, 0, 2, 1][n];
%o A064532 a(n) = if (n, my(d=digits(n)); sum(i=1, #d, h(d[i]+1)), 1); \\ _Michel Marcus_, Nov 11 2022
%Y A064532 Cf. A064529, A064530. Equals A064531 - 1.
%Y A064532 Cf. A358439 (sum by number of digits).
%K A064532 nonn,easy,base
%O A064532 0,9
%A A064532 _N. J. A. Sloane_, Oct 07 2001
%E A064532 More terms from _Matthew Conroy_, Oct 09 2001