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A058294
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Successive rows of a triangle, the columns of which are generalized Fibonacci sequences S(j).
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10
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1, 1, 1, 1, 1, 2, 3, 2, 1, 1, 3, 7, 10, 7, 3, 1, 1, 4, 13, 30, 43, 30, 13, 4, 1, 1, 5, 21, 68, 157, 225, 157, 68, 21, 5, 1, 1, 6, 31, 130, 421, 972, 1393, 972, 421, 130, 31, 6, 1, 1, 7, 43, 222, 931, 3015, 6961, 9976, 6961, 3015, 931, 222, 43, 7, 1
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OFFSET
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1,6
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COMMENTS
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T(n,k) = A102472(n,k-n+1), k=n..2*n-1;
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LINKS
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FORMULA
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The j-th column S(j) is generated by a(n+1) = (n+j)*a(n) + a(n-1), a(0)=0, a(1)=1.
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EXAMPLE
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Triangle begins:
1;
1, 1, 1;
1, 2, 3, 2, 1;
1, 3, 7, 10, 7, 3, 1;
...
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MATHEMATICA
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t[n_, n_] = 1; t[n_, k_] := t[n, k] = If[n<k, 0, (n-1)*t[n-1, k] + t[n-2, k]]; row[n_] := With[{ro = Table[t[n, k], {k, 1, n}]}, Join[Reverse[ro], Rest[ro]]]; Array[row, 8] // Flatten (* Jean-François Alcover, Oct 05 2016 *)
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PROG
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(Haskell)
a058294 n k = a058294_tabf !! (n-1) !! (k-1)
a058294_row n = a058294_tabf !! (n-1)
a058294_tabf = [1] : zipWith (++) xss (map (tail . reverse) xss)
where xss = tail a102473_tabl
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CROSSREFS
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KEYWORD
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nonn,tabf,nice,easy
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AUTHOR
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STATUS
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approved
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