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A106242 Same triangle as A106243, but with rows read in boustrophedon manner, i.e., in the order in which they were created.

%I A106242 #21 Jul 26 2017 03:15:29
%S A106242 1,0,1,0,1,1,0,2,3,3,0,6,11,13,13,0,26,50,67,73,73,0,146,286,403,479,
%T A106242 505,505,0,1010,1994,2876,3565,3997,4143,4143,0,8286,16426,23988,
%U A106242 30429,35299,38303,39313,39313,0,78626,156242,229844,295572,349989,390403,415115,423401,423401
%N A106242 Same triangle as A106243, but with rows read in boustrophedon manner, i.e., in the order in which they were created.
%H A106242 Alois P. Heinz, <a href="/A106242/b106242.txt">Table of n, a(n) for n = 0..10010</a>
%p A106242 T:= proc(n, k) option remember;
%p A106242       local t;
%p A106242       if n<1 or k<1 then 0
%p A106242     elif n=1 and k=1 then 1
%p A106242     elif n=1 and irem(k, 2)=1 or k=1 and irem(n, 2)=0 then 0
%p A106242     else t:= 1-2*irem(n+k, 2);
%p A106242              T(n-t, k+t) + T(n, k-1)+T(n-1, k)
%p A106242       fi
%p A106242     end:
%p A106242 seq (`if` (irem(d, 2)=1,
%p A106242   seq (T(d-k, k), k=1..d-1),
%p A106242   seq (T(n, d-n), n=1..d-1)), d=2..11);  # _Alois P. Heinz_, Feb 08 2011
%t A106242 T[n_, k_] := T[n, k] = Module[{t}, Which[n<1 || k<1, 0, n == 1 && k == 1, 1, n == 1 && Mod[k, 2] == 1 || k == 1 && Mod[n, 2] == 0, 0, True, t = 1 - 2*Mod[n+k, 2]; T[n-t, k+t] + T[n, k-1] + T[n-1, k]]]; Table[If[Mod[d, 2] == 1, Table[T[d-k, k], {k, 1, d-1}], Table[T[n, d-n], {n, 1, d-1}]], {d, 2, 11}] // Flatten (* _Jean-François Alcover_, Jan 14 2014, translated from _Alois P. Heinz_'s Maple code *)
%Y A106242 Right-hand diagonal is A059294. Cf. A106243. Row sums give A106327.
%K A106242 nonn,tabl,easy
%O A106242 0,8
%A A106242 _N. J. A. Sloane_, May 29 2005
%E A106242 More terms from _Alois P. Heinz_, Feb 08 2011