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Number of ways to move elements of an nXnXn triangular array to themselves or a neighbor, with no more than 1-1 elements moved to themselves.
0

%I #6 Apr 12 2016 09:03:04

%S 0,2,4,132,3440,358792,71771952,39547904272,51276433391328,

%T 167894702548149600,1348410361035047416704

%N Number of ways to move elements of an nXnXn triangular array to themselves or a neighbor, with no more than 1-1 elements moved to themselves.

%C Column 1 of A271684.

%e Some solutions for n=4

%e .....5........6........6........5........5........5........6........6

%e ....5.1......6.1......6.1......2.6......4.1......6.1......2.6......2.3

%e ...5.2.5....2.6.6....5.1.6....5.2.6....6.4.3....5.2.6....5.1.6....5.6.6

%e ..4.2.4.1..2.3.3.1..4.1.2.3..2.2.3.3..2.3.4.3..4.1.2.3..4.1.1.3..2.2.3.1

%e Element moves: 0=itself 1=nw 2=ne 3=w 4=e 5=sw 6=se, reciprocals total 7

%Y Cf. A271684.

%K nonn

%O 1,2

%A _R. H. Hardin_, Apr 12 2016