A238365 Number of dots needed to express n as a Roman numeral in Braille.

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, 18, 14, 12, 14, 16, 18, 18, 16, 18, 20, 22, 18, 7, 9, 11, 13, 13, 11, 13, 15, 17, 13, 3, 5, 7, 9, 9, 7, 9, 11, 13, 9, 7, 9, 11, 13, 13, 11, 13, 15, 17, 13, 11, 13, 15

Offset

1,1

Links

Table of n, a(n) for n=1..72.

Wikipedia, Braille

Example

VII in Braille (with the "Roman num" character):
  o  o      o    o
     o    o    o
  o  o o
Therefore a(7) = 10 - 2 = 8.

Prog

(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));
(PARI)
/* The program works for n < 40 */
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, ", "));

Crossrefs

Cf. also A002963, A048181, A030166, A072283, A079399, A121018, A220090.

Sequence in context: A011031 A248844 A257821 * A259935 A054584 A049041

Adjacent sequences: A238362 A238363 A238364 * A238366 A238367 A238368

Keyword

nonn,word,base

Author

Arkadiusz Wesolowski, Feb 25 2014

Status

approved