A280913 Number of dots in International Morse numeral representation of n.

0, 1, 2, 3, 4, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2

Offset

0,3

Comments

The Morse Code is written in current ITU standard.

For the number of dashes see A280916.

Links

Indranil Ghosh, Table of n, a(n) for n = 0..10000

Wikipedia, Morse code

Wikipedia, International Telecommunication Union

Formula

a(n) = A268643(A060109(n)) = floor(1+n/10)*5 - A280916(n) = a(floor(n/10)) + a(n%10) if n > 9 or min(n, 10-n) = 5 - |5 - n| otherwise, where % is the modulo (remainder) operator. - M. F. Hasler, Jun 22 2020

Example

For n = 4, the Morse numeral representation of 4 is "....-" i.e., 4 dots. So, a(4) = 4.
For n = 26, the Morse numeral representation of 26 is "..--- -...." i.e, 6 dots. So, a(26) = 6.

Mathematica

Table[Total[IntegerDigits[n]/.{6->4, 7->3, 8->2, 9->1}], {n, 0, 120}] (* Harvey P. Dale, Feb 06 2020 *)

Prog

(Python)
M={"1":".----", "2":"..---", "3":"...--", "4":"....-", "5":".....", "6":"-....", "7":"--...", "8":"---..", "9":"----.", "0":"-----"}
def A280913(n):
    z="".join(M[i] for i in str(n))
    return z.count(".")
print([A280913(n) for n in range(101)])
(PARI) apply( {A280913(n)=if(n>9, self()(n\10)+self()(n%10), 5-abs(n-5))}, [0..88]) \\ M. F. Hasler, Jun 22 2020

Crossrefs

Cf. A060109 (Morse code for n), A280916 (number of dashes), A268643 (number of '1's in n).

Cf. A006968, A278182.

Sequence in context: A271751 A017890 A134011 * A035343 A017880 A086144

Adjacent sequences: A280910 A280911 A280912 * A280914 A280915 A280916

Keyword

nonn,base

Author

Indranil Ghosh, Jan 10 2017

Status

approved