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Reversed inversion vectors for the permutations of A060117, presented as pseudo-decimal numbers.
3

%I #3 May 01 2014 02:48:25

%S 0,1,10,11,21,20,100,101,110,111,121,120,210,211,200,201,220,221,311,

%T 310,321,320,301,300,1000,1001,1010,1011,1021,1020,1100,1101,1110,

%U 1111,1121,1120,1210,1211,1200,1201,1220,1221,1311,1310,1321,1320,1301,1300

%N Reversed inversion vectors for the permutations of A060117, presented as pseudo-decimal numbers.

%C If one uses the ordering of A055089 instead of A060117 (procedure PermRevLexUnrank instead of PermUnrank3R) one gets A007623 (Integers written in factorial base) which is a permutation of this sequence.

%p [seq(SiteSwap2ToDec(Perm2InversionVector(PermUnrank3R(j))),j=0..119)];

%p Perm2InversionVector := proc(p) local n,i,j,a,c; n := nops(p); a := []; for i from 2 to n do c := 0; for j from 1 to i-1 do if(p[j] > p[i] then c := c+1; fi; od; a := [op(a),c]; od; RETURN(a); end;

%Y SiteSwap2ToDec procedure given in A060496 and PermUnrank3R in A060117.

%K nonn,base

%O 1,3

%A _Antti Karttunen_, Aug 23 2001