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 A094669 Number of halving and tripling steps for 10^n to reach 1 in '3x+1' problem. 1
 6, 25, 111, 29, 128, 152, 145, 107, 100, 124, 347, 146, 289, 194, 275, 255, 235, 303, 340, 470, 357, 324, 454, 266, 564, 433, 470, 331, 492, 467, 584, 515, 614, 550, 711, 497, 653, 1039, 577, 694, 749, 755, 779, 666, 752, 913, 769, 754, 724, 691, 883, 827, 683 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Michael S. Branicky, Table of n, a(n) for n = 1..10000 Index entries for sequences related to 3x+1 (or Collatz) problem FORMULA a(n) = A006577(A011557(n)). - Michel Marcus, Jun 25 2021 PROG (Python) def f(x): return x//2 if x%2 == 0 else 3*x + 1 def a(n): i, c = 10**n, 0 while i != 1: i, c = f(i), c+1 return c print([a(n) for n in range(1, 54)]) # Michael S. Branicky, Jun 25 2021 CROSSREFS Cf. A006577, A011557. Sequence in context: A048875 A295202 A346894 * A100296 A346818 A120758 Adjacent sequences: A094666 A094667 A094668 * A094670 A094671 A094672 KEYWORD easy,nonn AUTHOR Jason Earls, Jun 07 2004 EXTENSIONS a(53) and beyond from Michael S. Branicky, Jun 25 2021 STATUS approved

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Last modified December 4 07:54 EST 2023. Contains 367557 sequences. (Running on oeis4.)