%I A075486
%S A075486 8,6,20,13,27,28,122,123,36,37,157,114,53,54,99,100,101,102,103,73,167,
%T A075486 168,169,170,171,172,248,174,188,189,252,253,179,180,318,244,196,197,
%U A075486 154,155,156,157,401,327,496,497,162,163,332,333,409,472,411,412,338
%N A075486 Length of iteration list when Collatz-function is iterated with initial 
               value -1+2^n.
%C A075486 n=4,1+2^n=17,list={17,52,26,13,40,20,10,5,16,8,4,2,1}, so a(4)=13.
%F A075486 a(n)=A008908(2^n+1)
%Y A075486 Cf. A006370, A008908, A074472, A075487-A075488.
%Y A075486 Sequence in context: A119876 A036176 A064685 this_sequence A123875 A058088 
               A112145
%Y A075486 Adjacent sequences: A075483 A075484 A075485 this_sequence A075487 A075488 
               A075489
%K A075486 nonn
%O A075486 1,1
%A A075486 Labos E. (labos(AT)ana.sote.hu), Sep 26 2002