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%I #14 Aug 27 2016 12:52:45
%S 0,2,1,32,31,21,432,431,421,321,5432,5431,5421,5321,4321,65432,65431,
%T 65421,65321,64321,54321,765432,765431,765421,765321,764321,754321,
%U 654321,8765432,8765431,8765421,8765321,8764321,8754321,8654321,7654321
%N Triangle read by rows: the n-th row contains n numbers sorted in decreasing value, each build by dropping a different number from the sequence [n,n-1,n-2,....,1] and concatenating the n-1 others. By definition the first row contains 0.
%H Harvey P. Dale, <a href="/A081541/b081541.txt">Table of n, a(n) for n = 1..10000</a>
%e Triangle begins:
%e 0;
%e 2,1;
%e 32,31,21;
%e 432,431,421,321;
%e 5432,5431,5421,5321,4321;
%e 65432,65431,...
%p conca := proc(S) local resul,d,i ; resul := 0 ; for i from 1 to nops(S) do d := ilog10(op(i,S))+1 ; resul := resul*10^d+op(i,S) ; od ; resul ; end: A081541 := proc(row) local a,p,i; if row =1 then RETURN([0]) ; fi ; a := [] ; p := [seq(row+1-i,i=1..row)] ; for i from 1 to row do a := [op(a),conca(subsop(i=NULL,p))] ; od: sort(a,`>`)[1..row] ; end: seq(op(A081541(n)),n=1..10) ; # _R. J. Mathar_, Jul 15 2007
%t Table[Reverse[FromDigits/@Table[Drop[Range[k,1,-1],{n}],{n,1,k}]],{k,8}]//Flatten (* _Harvey P. Dale_, Aug 27 2016 *)
%Y Cf. A081539, A081540, A081542.
%K base,nonn,tabl
%O 1,2
%A _Amarnath Murthy_, Mar 29 2003
%E More terms from _R. J. Mathar_, Jul 15 2007
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