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%I #12 Oct 13 2022 13:01:51
%S 17,188,94,47,518,259,37,408,204,102,51,17,188,94,47,518,259,37,408,
%T 204,102,51,17,188,94,47,518,259,37,408,204,102,51,17,188,94,47,518,
%U 259,37,408,204,102,51,17,188,94,47,518,259,37,408,204,102,51,17,188,94,47,518,259,37,408,204,102,51
%N a(n+1) = a(n)/2 if 2|a(n), a(n)/3 if 3|a(n), a(n)/5 if 5|a(n), a(n)/7 if 7|a(n), otherwise 11*a(n)+1.
%C This is the '11x+1' map. The 'Px+1 map': if x is divisible by any prime < P then divide out these primes one at a time starting with the smallest; otherwise multiply x by P and add 1.
%C Sequence has period 11. - _Alois P. Heinz_, Jan 19 2021
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CollatzProblem.html">Collatz problem</a>
%H <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,1).
%Y Cf. A057446, A057216, A057522, A057534.
%K nonn,easy
%O 0,1
%A Murad A. AlDamen (Divisibility(AT)yahoo.com), Oct 17 2000