cp's OEIS Frontend

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

%I A280913 #28 May 01 2021 08:02:53
%S A280913 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,
%T A280913 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,
%U A280913 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
%N A280913 Number of dots in International Morse numeral representation of n.
%C A280913 The Morse Code is written in current ITU standard.
%C A280913 For the number of dashes see A280916.
%H A280913 Indranil Ghosh, <a href="/A280913/b280913.txt">Table of n, a(n) for n = 0..10000</a>
%H A280913 Wikipedia, <a href="http://en.wikipedia.org/wiki/Morse_code">Morse code</a>
%H A280913 Wikipedia, <a href="https://en.wikipedia.org/wiki/International_Telecommunication_Union">International Telecommunication Union</a>
%F A280913 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
%e A280913 For n = 4, the Morse numeral representation of 4 is "....-" i.e., 4 dots. So, a(4) = 4.
%e A280913 For n = 26, the Morse numeral representation of 26 is "..--- -...." i.e, 6 dots. So, a(26) = 6.
%t A280913 Table[Total[IntegerDigits[n]/.{6->4,7->3,8->2,9->1}],{n,0,120}] (* _Harvey P. Dale_, Feb 06 2020 *)
%o A280913 (Python)
%o A280913 M={"1":".----","2":"..---","3":"...--","4":"....-","5":".....","6":"-....","7":"--...","8":"---..","9":"----.","0":"-----"}
%o A280913 def A280913(n):
%o A280913     z="".join(M[i] for i in str(n))
%o A280913     return z.count(".")
%o A280913 print([A280913(n) for n in range(101)])
%o A280913 (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
%Y A280913 Cf. A060109 (Morse code for n), A280916 (number of dashes), A268643 (number of '1's in n).
%Y A280913 Cf. A006968, A278182.
%K A280913 nonn,base
%O A280913 0,3
%A A280913 _Indranil Ghosh_, Jan 10 2017