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%I #10 Dec 31 2020 02:12:11
%S 1,2,3,6,11,19,30,44,68,112,176,271,411,602,851,1232,1783,2530,3567,
%T 4996,6838,9279,12463,16597,21848,28227,35682,44464,54597,65966,78433,
%U 91725,104896,116966,126335,131998,133107,128720,119332,106335,91545,75742,60119,45840,33422,23223,15140,9094,5073,2605,1224,528,225,75,20,2
%N Number of configurations of the 5 X 2 variant of Sam Loyd's 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 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/result52.txt">No. 52 (9 puzzles)</a>.
%e Starting from
%e 12345
%e 6789-
%e the 2 most distant configurations corresponding to a(55)=2 are
%e -9371 and -5321
%e 54826.....94876
%o See link in A089473.
%o (Python) # alst(), moves(), swap() in A089473
%o print(alst("-123456789", (5, 2))) # _Michael S. Branicky_, Dec 30 2020
%Y Cf. A087725, A089473. Index of last sequence term: A090033. Other nonsquare sliding block puzzles: A090034, A090035, A090166, A090167.
%K fini,full,nonn
%O 0,2
%A _Hugo Pfoertner_, Nov 27 2003