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A249768 Row "sums" of triangle A245618, using the operation <+> defined in A245618.

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%I A249768 #9 Nov 14 2014 13:12:46
%S A249768 1,2,2,2,2,10,8,2,2,58,104,186,292,442,410,2,2,3434,6856,13674,27192,
%T A249768 53912,105770,205628,389108,732762,1286970,2181624,3237606,5206764,
%U A249768 4527418,2204,2,40384330,80768648,161537226,323074168,646146872,1292283522,2584509436
%N A249768 Row "sums" of triangle A245618, using the operation <+> defined in A245618.
%H A249768 Peter J. C. Moses, <a href="/A249768/b249768.txt">Table of n, a(n) for n = 0..499</a>
%e A249768 For n=6 we have the following row of triangle A245618: 1  2  3  8  3  2  1.
%e A249768 We have 1<+>2=1, 1<+>3=4, 4<+>8=12, 12<+>3=9, 9<+>2=7, 7<+>1=8. So, a(6)=8.
%t A249768 parityAdd[a_,b_]:=Abs[a+b (-1)^(a+b)];
%t A249768 t[n_,0]:=1;
%t A249768 t[n_,n_]:=1;
%t A249768 t[n_,k_]:=t[n,k]=parityAdd[t[n-1,k-1],t[n-1,k]];
%t A249768 Map[Fold[parityAdd,First[#],Rest[#]]&,Table[t[n,k],{n,0,40},{k,0,n}]] (* _Peter J. C. Moses_, Nov 05 2014 *)
%Y A249768 Cf. A245618, A245619.
%K A249768 nonn
%O A249768 0,2
%A A249768 _Vladimir Shevelev_, Nov 05 2014
%E A249768 More terms from _Peter J. C. Moses_, Nov 05 2014