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C. A. Pickover, The Math Book, Sterling, NY, 2009; see p. 374.
Table of n, a(n) for n=0..97.
Index entries for sequences related to 3x+1 (or Collatz) problem
Index entries for linear recurrences with constant coefficients, signature (0, 0, 1).
f:=proc(n) if n mod 2 = 0 then n/2 else 3*n+1; fi; end; g:=proc(n) local i, t1; t1:=[n]; for i from 1 to 120 do t1:=[op(t1), f(t1[nops(t1)])]; od; t1; end; g(3);
(PARI) a(n)=if(n>4, [2, 1, 4][n%3+1], [3, 10, 5, 16, 8][n+1]) \\ Charles R Greathouse IV, Jun 22 2016
Sequence in context: A247034 A275511 A035411 * A246777 A111127 A140948
Adjacent sequences: A033475 A033476 A033477 * A033479 A033480 A033481