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A001404
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Triangle of values of 2-d recurrence.
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1
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1, 1, 1, 2, 2, 1, 4, 5, 2, 1, 9, 11, 5, 2, 1, 20, 25, 12, 5, 2, 1, 45, 57, 27, 12, 5, 2, 1, 102, 129, 62, 28, 12, 5, 2, 1, 231, 293, 141, 64, 28, 12, 5, 2, 1, 524, 665, 321, 146, 65, 28, 12, 5, 2, 1, 1189, 1510, 729, 333, 148, 65, 28, 12, 5, 2, 1, 2699, 3428, 1656
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OFFSET
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0,4
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COMMENTS
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The first column of the triangle (see example) appears to be A167750. [Joerg Arndt, Jul 09 2012]
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LINKS
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EXAMPLE
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Triangle starts
1,
1, 1,
2, 2, 1,
4, 5, 2, 1,
9, 11, 5, 2, 1,
20, 25, 12, 5, 2, 1,
45, 57, 27, 12, 5, 2, 1,
102, 129, 62, 28, 12, 5, 2, 1,
231, 293, 141, 64, 28, 12, 5, 2, 1,
524, 665, 321, 146, 65, 28, 12, 5, 2, 1,
1189, 1510, 729, 333, 148, 65, 28, 12, 5, 2, 1,
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MAPLE
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a[ 0, 0 ] := 1; for i from 1 to N do a[ i, 0 ] := a[ i-1, 0 ]+a[ i-1, 1 ]; for j from 1 to i do a[ i, j ] := sum(a[ i-j, t ], t=0..min(j+1, N)) od; od;
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PROG
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(PARI) T(m, n)=if(m<n, 0, if(m==0&&n==0, 1, if(n==0, T(m-1, 0)+T(m-1, 1), sum(t=0, n+1, T(m-n, t))))) /* Ralf Stephan */
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CROSSREFS
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KEYWORD
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AUTHOR
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N. J. A. Sloane [ I have temporarily mislaid the name of the person who sent this ]
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EXTENSIONS
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STATUS
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approved
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