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%I #28 May 01 2021 08:04:04
%S 5,4,3,2,1,0,1,2,3,4,9,8,7,6,5,4,5,6,7,8,8,7,6,5,4,3,4,5,6,7,7,6,5,4,
%T 3,2,3,4,5,6,6,5,4,3,2,1,2,3,4,5,5,4,3,2,1,0,1,2,3,4,6,5,4,3,2,1,2,3,
%U 4,5,7,6,5,4,3,2,3,4,5,6,8,7,6,5,4,3,4,5,6,7,9,8,7,6,5,4,5,6,7,8,14
%N Number of dashes in International Morse numeral representation of n.
%C The Morse Code is written in current ITU standard.
%H Indranil Ghosh, <a href="/A280916/b280916.txt">Table of n, a(n) for n = 0..10000</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Morse_code">Morse code</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/International_Telecommunication_Union">International Telecommunication Union</a>
%F a(n) = A316863(A060109(n)) = floor(1+n/10)*5 - A280913(n) = a(floor(n/10)) + a(n%10) if n > 9 or |5 - n| otherwise, where % is the modulo (remainder) operator. - _M. F. Hasler_, Jun 22 2020
%e For n = 4, the Morse numeral representation of 4 is "....-" i.e., 1 dash. So, a(4) = 1.
%e For n = 26, the Morse numeral representation of 26 is "..--- -...." i.e, 4 dashes. So, a(26) = 4.
%t Array[Total@ Map[Abs[# - 5] &, IntegerDigits[#]] &, 101, 0] (* _Michael De Vlieger_, Jun 28 2020 *)
%o (Python)
%o M={"1":".----","2":"..---","3":"...--","4":"....-","5":".....","6":"-....","7":"--...","8":"---..","9":"----.","0":"-----"}
%o def A280916(n):
%o z="".join(M[i] for i in str(n))
%o return z.count("-")
%o print([A280916(n) for n in range(100)])
%o (PARI) apply( {A280916(n)=if(n>9, self()(n\10)+self()(n%10), abs(n-5))}, [0..88]) \\ _M. F. Hasler_, Jun 22 2020
%Y Cf. A060109 (Morse code of n), A280913 (number of dots).
%Y Cf. A006968, A278182 (for Roman resp. Maya representation of n).
%K nonn,base
%O 0,1
%A _Indranil Ghosh_, Jan 10 2017
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