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%I #15 Dec 31 2016 01:04:38
%S 1,0,1,2,1,0,0,2,3,5,15,12,8,5,0,0,15,27,39,48,55,239,221,190,152,103,
%T 55,0,0,239,460,680,871,1025,1137,1199,6810,6553,6062,5374,4493,3471,
%U 2336,1199,0,0,6810,13363,19903,25958,31351,35884,39399,41847
%N The array in A059219 read by antidiagonals in 'up' direction.
%H G. C. Greubel, <a href="/A059220/b059220.txt">Table of n, a(n) for the first 50 rows, flattened</a>
%H <a href="/index/Bo#boustrophedon">Index entries for sequences related to boustrophedon transform</a>
%e The array begins
%e 1 1 0 5 0 55 0 ...
%e 0 1 3 5 48 55 ...
%e 2 2 8 39 103 ...
%e 0 12 27 152 ...
%e 15 15 190 ...
%e 0 221 ...
%p See A059219 for Maple code.
%t max = 9; t[0, 0] = 1; t[0, _?EvenQ] = 0; t[_?OddQ, 0] = 0; t[n_, k_] /; OddQ[n + k] (* up *) := t[n, k] = t[n+1, k-1] + Sum[t[n, j], {j, 0, k-1}]; t[n_, k_] /; EvenQ[n + k] (* down *) := t[n, k] = t[n-1, k+1] + Sum[t[j, k], {j, 0, n-1}]; Table[t[n - k, k], {n, 0, max}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Aug 19 2013 *)
%Y Cf. A000667, A059216, A059219, A059217, A059235.
%K easy,nonn,tabl,nice
%O 1,4
%A _N. J. A. Sloane_, Jan 18 2001
%E More terms from _Floor van Lamoen_, Jan 19 2001
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