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A191780 Triangle G(n,k): the value of n written in base k with digits reversed (but written here in base 10) for 2 <= k <= n.

%I A191780 #26 Feb 10 2018 17:53:44
%S A191780 1,3,1,1,4,1,5,7,5,1,3,2,9,6,1,7,5,13,11,7,1,1,8,2,16,13,8,1,9,1,6,21,
%T A191780 19,15,9,1,5,10,10,2,25,22,17,10,1,13,19,14,7,31,29,25,19,11,1,3,4,3,
%U A191780 12,2,36,33,28,21,12,1,11,13,7,17,8,43,41,37,31,23,13,1,7,22,11,22,14,2,49,46,41,34,25,14,1,15,7,15,3
%N A191780 Triangle G(n,k): the value of n written in base k with digits reversed (but written here in base 10) for 2 <= k <= n.
%e A191780 The triangle starts
%e A191780   1;
%e A191780   3, 1;
%e A191780   1, 4, 1;
%e A191780   5, 7, 5, 1;
%e A191780   3, 2, 9, 6, 1;
%p A191780 A191780 := proc(n,k) d := ListTools[Reverse](convert(n,base,k)) ; add( op(i,d)*k^(i-1),i=1..nops(d)) ;
%p A191780 end proc: # _R. J. Mathar_, Aug 26 2011
%t A191780 G[n_, k_] := IntegerDigits[n, k] // Reverse // FromDigits[#, k]&; Table[ G[n, k], {n, 2, 15}, {k, 2, n}] // Flatten (* _Jean-François Alcover_, Feb 10 2018 *)
%Y A191780 Cf. A007088..A007095, A030101 (column k=2), A030102 (column k=3), A030103 (column k=4).
%K A191780 nonn,tabl,base,easy
%O A191780 2,2
%A A191780 _Juri-Stepan Gerasimov_, Aug 02 2011
%E A191780 Corrected by _R. J. Mathar_, Aug 26 2011