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%I #14 Jan 01 2021 03:21:50
%S 1,2,3,6,11,20,36,60,95,155,258,426,688,1106,1723,2615,3901,5885,8851,
%T 13205,19508,28593,41179,58899,83582,118109,165136,228596,312542,
%U 423797,568233,755727,994641,1296097,1667002,2119476,2660415,3300586,4038877
%N Number of configurations of the 6 X 2 variant of the so-called "Sam Loyd" sliding block 15-puzzle that require a minimum of n moves to be reached, starting with the empty square in one of the corners.
%H Herman Jamke, <a href="/A090167/b090167.txt">Table of n, a(n) for n = 0..80</a> (complete sequence)
%H Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/sbpnx2.txt">Solutions of small n*2 sliding block puzzles.</a>
%H Takaken, <a href="http://www.ic-net.or.jp/home/takaken/nt/slide/index.html">11-Puzzle Page</a>.
%H Takaken, <a href="http://www.ic-net.or.jp/home/takaken/nt/slide/result62.txt">No. 62 (11 puzzles)</a>.
%o See link in A089473.
%o (Python) # alst(), moves(), swap() in A089473
%o alst("-123456789AB", (6, 2), v=True) # _Michael S. Branicky_, Dec 31 2020
%Y Cf. A087725, A089473. Index of last sequence term: A090033. Other nonsquare sliding block puzzles: A090034, A090035, A090036, A090166.
%K fini,full,nonn
%O 0,2
%A _Hugo Pfoertner_, Nov 27 2003
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Oct 22 2006