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%I #6 Dec 05 2013 19:56:53
%S 1,3,2,4,5,6,7,9,10,8,11,12,13,14,15,16,17,18,19,21,20,22,23,24,25,28,
%T 26,27,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45
%N Triangle read by rows which contains in row n that permutation of the n numbers T(n-1)+1..T(n) which yields a smallest multiple of n after concatenation. T(n) are the triangular numbers. If no such multiple exists, the row contains zeros.
%C Conjecture: No term is zero.
%e Terms a(7) to a(10) are 7,9,10,8 respectively, a permutation of 7,8,9 and 10, the next four numbers and 79108 is a multiple of 4.
%e The 4th row contains a permutation of 7, 8, 9 and 10, the four numbers up to and including T(4)=A000217(4)=10. The concatenations 78910, 78109 etc. are not multiples of 4, which leaves the concatenation 79108 as the only (and therefore minimal) candidate for the ordering of the numbers in the row. Triangle starts
%e 1;
%e 3,2;
%e 4,5,6;
%e 7,9,10,8;
%e 11,12,13,14,15;
%e 16,17,18,19,21,20;
%Y Cf. A096136.
%K base,more,nonn,tabl
%O 1,2
%A _Amarnath Murthy_, Jul 06 2004
%E More terms from _R. J. Mathar_, Aug 03 2007
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