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A066201 Array read by antidiagonals upwards: for n-th row (n>=0), T(n,0) = 1; for k > 0, T(n,k) = T(n,k-1)-(n+k-1) if this is positive and has not already appeared in this row, otherwise T(n,k) = T(n,k-1)+(n+k-1).

%I A066201 #23 May 19 2019 20:38:35
%S A066201 1,1,1,1,2,2,1,3,4,4,1,4,6,7,7,1,5,8,2,3,3,1,6,10,3,7,8,8,1,7,12,4,9,
%T A066201 13,14,14,1,8,14,5,11,2,20,21,21,1,9,16,6,13,3,10,12,13,13,1,10,18,7,
%U A066201 15,4,12,19,21,22,22,1,11,20,8,17,5,14,2,29,11,12,12
%N A066201 Array read by antidiagonals upwards: for n-th row (n>=0), T(n,0) = 1; for k > 0, T(n,k) = T(n,k-1)-(n+k-1) if this is positive and has not already appeared in this row, otherwise T(n,k) = T(n,k-1)+(n+k-1).
%H A066201 Seiichi Manyama, <a href="/A066201/b066201.txt">Antidiagonals n = 0..139, flattened</a>
%H A066201 <a href="/index/Rea#Recaman">Index entries for sequences related to Recamán's sequence</a>
%e A066201 Array begins
%e A066201    1, 1,  2, 4,  7,  3,  8, 14, 21, 13, ...
%e A066201    1, 2,  4, 7,  3,  8, 14, 21, 13, 22, ...
%e A066201    1, 3,  6, 2,  7, 13, 20, 12, 21, 11, ...
%e A066201    1, 4,  8, 3,  9,  2, 10, 19, 29, 18, ...
%e A066201    1, 5, 10, 4, 11,  3, 12,  2, 13, 25, ...
%e A066201    1, 6, 12, 5, 13,  4, 14,  3, 15,  2, ...
%e A066201    1, 7, 14, 6, 15,  5, 16,  4, 17,  3, ...
%e A066201    1, 8, 16, 7, 17,  6, 18,  5, 19,  4, ...
%t A066201 T[_, 0] = 1; T[n_, k_] := T[n, k] = If[t = T[n, k-1] - (n+k-1); t > 0 && FreeQ[Table[T[n, j], {j, 0, k-1}], t], t, T[n, k-1] + (n+k-1)]; Table[ T[n-k, k], {n, 0, 12}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Feb 18 2018 *)
%Y A066201 Rows give A063733, A063733, A005132, A066199, A066200.
%K A066201 nonn,easy,tabl,look
%O A066201 0,5
%A A066201 _N. J. A. Sloane_, Dec 16 2001
%E A066201 More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 05 2003