This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A153114 #15 Jun 19 2021 17:58:29 %S A153114 0,1,3,7,15,30,31,63,127,255,503,507,509,510,511,1003,1005,1006,1015, %T A153114 1019,1020,1021,1022,2007,2015,2030,2031,2039,2043,2045,2046,3007, %U A153114 3070,3071,4030,4031,4063,4079,4087,4090,4091,4093,4094,8063,8190,8191,16383 %N A153114 Integers with the same number of zeros in base 10 and base 2. %C A153114 Some have no zeros at all. These are exclusively of the form 2^n-1, but not universally. 511=111111111b, no zeros. 1023=1111111111b but zero counts are inequal. The smallest integer with 6 zeros in both decimal and binary expansion is 100007900=101111101011111111111011100b. %H A153114 Giovanni Resta, <a href="/A153114/b153114.txt">Table of n, a(n) for n = 1..10000</a> (first 550 terms from Enrique Pérez Herrero) %e A153114 a(6)=30 because 30 base 2 = 11110 and both terms have the same number of zeros. %t A153114 Select[Range[0,20000],DigitCount[#,10,0]==DigitCount[#,2,0]&] (* _Harvey P. Dale_, Jun 19 2021 *) %Y A153114 Cf. A023416, A153115. %K A153114 nonn,base %O A153114 1,3 %A A153114 _Gil Broussard_, Dec 18 2008