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 A138824 #10 Oct 12 2016 16:11:38 %S A138824 1,10,100,1000,10000,100000,1111111,11111110,111111100,1111111000, %T A138824 11111110000,111111100000 %N A138824 Divisors of 4064 (the 4th perfect number divided by 2), written in base 2. %C A138824 a(n) has n digits. See A138814 for more information. %H A138824 <a href="/index/Di#divisors">Index entries for sequences related to divisors of numbers</a> %e A138824 The structure of divisors of 4064 (see A138814) %e A138824 ................................................................. %e A138824 n ........... Divisor . Formula ....... Divisor written in base 2 %e A138824 ................................................................. %e A138824 1) ................ 1 = 2^0 ........... 1 %e A138824 2) ................ 2 = 2^1 ........... 10 %e A138824 3) ................ 4 = 2^2 ........... 100 %e A138824 4) ................ 8 = 2^3 ........... 1000 %e A138824 5) ............... 16 = 2^4 ........... 10000 %e A138824 6) A134708(4) = .. 32 = 2^5 ........... 100000 %e A138824 7) A000668(4) = . 127 = 2^7 - 2^0 ..... 1111111 %e A138824 8) .............. 254 = 2^8 - 2^1 ..... 11111110 %e A138824 9) .............. 508 = 2^9 - 2^2 ..... 111111100 %e A138824 10) ............ 1016 = 2^10- 2^3 ..... 1111111000 %e A138824 11) ............ 2032 = 2^11- 2^4 ..... 11111110000 %e A138824 12) A133028(4) = 4064 = 2^12- 2^5 ..... 111111100000 %t A138824 FromDigits/@(IntegerDigits[#,2]&/@Divisors[4064]) (* _Harvey P. Dale_, Oct 12 2016 *) %Y A138824 Perfect number divided by 2: A133028. Cf. A000043, A000396, A000668, A090748, A134708, A135654, A138814. %K A138824 easy,fini,full,nonn,less %O A138824 1,2 %A A138824 _Omar E. Pol_, Mar 31 2008