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A059235
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The array in A059219 read by antidiagonals in the direction in which it was constructed.
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1
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1, 0, 1, 0, 1, 2, 0, 2, 3, 5, 0, 5, 8, 12, 15, 0, 15, 27, 39, 48, 55, 0, 55, 103, 152, 190, 221, 239, 0, 239, 460, 680, 871, 1025, 1137, 1199, 0, 1199, 2336, 3471, 4493, 5374, 6062, 6553, 6810, 0, 6810, 13363, 19903, 25958, 31351, 35884, 39399, 41847, 43108, 0
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,6
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LINKS
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Table of n, a(n) for n=1..56.
Index entries for sequences related to boustrophedon transform
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EXAMPLE
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The array begins
1 1 0 5 0 55 0 ...
0 1 3 5 48 55 ...
2 2 8 39 103 ...
0 12 27 152 ...
15 15 190 ...
0 221 ...
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MATHEMATICA
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max = 10; 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[tn = Table[t[n-k, k], {k, 0, n}]; If[OddQ[n], tn, tn // Reverse] , {n, 0, max}] // Flatten (* Jean-François Alcover, Nov 20 2012 *)
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CROSSREFS
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Cf. A000667, A059216, A059219, A059217, A059220.
Sequence in context: A063180 A141693 A028376 * A222753 A072514 A071547
Adjacent sequences: A059232 A059233 A059234 * A059236 A059237 A059238
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KEYWORD
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easy,nonn,tabl,nice
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AUTHOR
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N. J. A. Sloane, Jan 18 2001
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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), Jan 24 2001
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STATUS
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approved
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