A091391 - OEIS

%I #5 Oct 09 2013 14:20:17

%S 1,4,11,16,7,12,16,6,8,13,1,5,10,16,1,5,9,15,2,4,7,12,16,5,9,14,2,6,1,

%T 8,10,15,3,7,12,0,6,10,4,10,15,0,3,8,12,14,7,9,14,3,8,10,13,2,4,7,12,

%U 16,5,7,16,1,6,12,16,6,11,0,4,6,15,0,3,5,9,13,8,15,0,5,10,14,2,9,14,1,7,11

%N Aronson's mod 17 sequence: "T is the first, fourth, eleventh, sixteenth, seventh, ... letter in this sentence, not counting spaces and commas and all mod 17".

%C Infinite? Periodic? It seems the answers are "Yes and No" because many numbers (such as "tenth") have multiple T's and moreover, in many of these, the T's are spread such that at least one of them will be != 2 mod 17 (2 is important because "second" is the only T-less word)

%D A. J. Aronson, quoted by D. R. Hofstadter in Metamagical Themas, Basic Books, NY, 1985, p. 44.

%H B. Cloitre, N. J. A. Sloane and M. J. Vandermast, <a href="http://www.cs.uwaterloo.ca/journals/JIS/index.html">Numerical analogues of Aronson's sequence</a>, J. Integer Seqs., Vol. 6 (2003), #03.2.2.

%Y Cf. A005224, A091387, A091388, A091389, A091390.

%K easy,nonn,word

%O 0,2

%A _Sam Alexander_, Jan 05 2004