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A067574 Array T(i,j) read by ascending antidiagonals, where T(i,j) is the concatenation of i and j (1<=i, 1<=j).

%I A067574 #17 Nov 21 2021 15:45:17
%S A067574 11,21,12,31,22,13,41,32,23,14,51,42,33,24,15,61,52,43,34,25,16,71,62,
%T A067574 53,44,35,26,17,81,72,63,54,45,36,27,18,91,82,73,64,55,46,37,28,19,
%U A067574 101,92,83,74,65,56,47,38,29,110,111,102,93,84,75,66,57,48,39,210,111
%N A067574 Array T(i,j) read by ascending antidiagonals, where T(i,j) is the concatenation of i and j (1<=i, 1<=j).
%C A067574 The antidiagonals are read in the opposite direction to those in A066686.
%F A067574 T(i, j) = i*10^A055642(i) + j. - _Michael S. Branicky_, Nov 21 2021
%e A067574 The array begins
%e A067574 11 12 13 14 15 16 17 18 19 110 ...
%e A067574 21 22 23 24 25 26 27 28 29 210 ...
%e A067574 31 32 33 34 35 36 37 38 39 310 ...
%e A067574 41 42 43 44 45 46 47 48 49 410 ...
%t A067574 a = {}; Do[ a = Append[a, ToExpression[ StringJoin[ ToString[i - j], ToString[j]]]], {i, 2, 13}, {j, 1, i - 1} ]; a
%o A067574 (Python)
%o A067574 def T(i, j): return int(str(i) + str(j))
%o A067574 def auptodiag(maxd):
%o A067574     return [T(d+1-j, j) for d in range(1, maxd+1) for j in range(1, d+1)]
%o A067574 print(auptodiag(12)) # _Michael S. Branicky_, Nov 21 2021
%Y A067574 Cf. A055642, A066686, A084854.
%K A067574 base,easy,nonn,tabl
%O A067574 1,1
%A A067574 _Robert G. Wilson v_, Jan 30 2002