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A084855 Triangular array, read by rows: T(n,k) = concatenated decimal representations of k and n, 1<=k<=n.

%I A084855 #17 Nov 21 2021 15:47:07
%S A084855 11,12,22,13,23,33,14,24,34,44,15,25,35,45,55,16,26,36,46,56,66,17,27,
%T A084855 37,47,57,67,77,18,28,38,48,58,68,78,88,19,29,39,49,59,69,79,89,99,
%U A084855 110,210,310,410,510,610,710,810,910,1010,111,211,311,411,511,611,711,811,911,1011,1111
%N A084855 Triangular array, read by rows: T(n,k) = concatenated decimal representations of k and n, 1<=k<=n.
%H A084855 Indranil Ghosh, <a href="/A084855/b084855.txt">Rows 1..100 of triangle, flattened</a>
%F A084855 T(n, k) = k*10^A055642(n) + n.
%F A084855 T(n, n) = A020338(n).
%o A084855 (Python)
%o A084855 def T(n, k): return int(str(k) + str(n))
%o A084855 def auptorow(maxrow):
%o A084855     return [T(n, k) for n in range(1, maxrow+1) for k in range(1, n+1)]
%o A084855 print(auptorow(11)) # _Michael S. Branicky_, Nov 21 2021
%Y A084855 Cf. A020338, A055642, A066686, A067574, A084854, A349520.
%K A084855 nonn,base,tabl
%O A084855 1,1
%A A084855 _Reinhard Zumkeller_, Jun 09 2003