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A228334
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Triangle read by rows: the X-transformation of the Catalan triangle A033184.
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3
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1, 0, 1, 0, 3, 1, 0, 14, 10, 1, 0, 84, 90, 21, 1, 0, 594, 825, 308, 36, 1, 0, 4719, 7865, 4004, 780, 55, 1, 0, 40898, 78078, 49686, 13650, 1650, 78, 1, 0, 379236, 804440, 606424, 214200, 37400, 3094, 105, 1, 0, 3711916, 8565960, 7379904, 3162816, 724812, 88179, 5320, 136, 1
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,5
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LINKS
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EXAMPLE
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Triangle begins:
1;
0, 1;
0, 3, 1;
0, 14, 10, 1;
0, 84, 90, 21, 1;
0, 594, 825, 308, 36, 1;
...
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MATHEMATICA
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nn = 9;
c[n_, k_] := Binomial[2n-k, n] (k+1)/(n+1);
a[0, 0] = 1;
a[n_, k_] := Table[c[n+k+i-1, 2k+j-1], {i, 1, 2}, {j, 1, 2}] // Det;
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PROG
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(PARI) C(n, k) = (k<=n)*binomial(2*n-k, n)*(k+1)/(n+1);
aX(nn) = {for (n = 0, nn, for (k = 0, n, print1(matdet(matrix(2, 2, i, j, C(n+k+i-1, 2*k+j-1))), ", "); ); print(); ); } \\ Michel Marcus, Feb 13 2014
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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A-number for Catalan triangle changed by Michel Marcus, Feb 13 2014
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STATUS
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approved
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