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%I #13 Sep 22 2014 06:04:04
%S 1,2,4,3,16,5,64,9,37,6,12,7,4096,22,76,129,65536,10,262144,13,25,35,
%T 24,60,301,1366,131329,15,117,39,1073741824,32769,81,21846,36,19,112,
%U 87382,40,94,6684,74,216,58,316,71,1176,49
%N a(n) is the minimal k such that a deck of 2k cards is returned to its original state by n out-shuffles.
%C The sequence continues with a(49)-a(80) = L, 126, 52, 27, 3181, 41, 357, 247, 16189, 30, 89976, 31, L, 357913942, 1789, 321, 126961, 34, 96853861, 69, 165, 107, 114240, 162, 220, 335, 2104, 115, 1461, 119, 1344, 1414 where L > 2*10^10. [_Lars Blomberg_, Sep 22 2014]
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Out-Shuffle.html">Out-Shuffle</a>
%K nonn,more
%O 1,2
%A _Eric W. Weisstein_, Jan 05 2006
%E Corrected a(31), added a(32)-a(48) by _Lars Blomberg_, Sep 22 2014