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 A238365 #10 Mar 08 2014 08:35:32 %S A238365 2,4,6,6,4,6,8,10,6,4,6,8,10,10,8,10,12,14,10,8,10,12,14,14,12,14,16, %T A238365 18,14,12,14,16,18,18,16,18,20,22,18,7,9,11,13,13,11,13,15,17,13,3,5, %U A238365 7,9,9,7,9,11,13,9,7,9,11,13,13,11,13,15,17,13,11,13,15 %N A238365 Number of dots needed to express n as a Roman numeral in Braille. %H A238365 Wikipedia, <a href="http://en.wikipedia.org/wiki/Braille">Braille</a> %e A238365 VII in Braille (with the "Roman num" character): %e A238365 o o o o %e A238365 o o o %e A238365 o o o %e A238365 Therefore a(7) = 10 - 2 = 8. %o A238365 (PARI) a=[2, 4, 6, 6, 4, 6, 8, 10, 6, 0]; b=[0, 4, 8, 12, 7, 3, 7, 11, 15, 6]; for(n=1, 72, if(n<100, print1(a[lift(Mod(n-1, 10))+1]+b[floor(n/10)+1], ", "), break)); %o A238365 (PARI) %o A238365 /* The program works for n < 40 */ %o A238365 b=0; for(n=1, 39, if(Mod(n, 10)==0, b=b+4); m=lift(Mod(n, 10)); a=2*m-6; if(Mod(m, 5)==4, d=abs(a-7)+b+1, if(m<4, d=a+b+6, d=a+b)); print1(d, ", ")); %Y A238365 Cf. also A002963, A048181, A030166, A072283, A079399, A121018, A220090. %K A238365 nonn,word,base %O A238365 1,1 %A A238365 _Arkadiusz Wesolowski_, Feb 25 2014