Number of dots and dashes used when representing n-th letter in Morse code.

Terms

a(0) =2a(1) =4a(2) =4a(3) =3a(4) =1a(5) =4a(6) =3a(7) =4a(8) =2a(9) =4a(10) =3a(11) =4a(12) =2a(13) =2a(14) =3a(15) =4a(16) =4a(17) =3a(18) =3a(19) =1a(20) =3a(21) =4a(22) =3a(23) =4a(24) =4a(25) =4