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A178122
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Triangle T(n,m) = A060187(n+1,m+1) + 2*binomial(n,m) - 2, read by rows.
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1
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1, 1, 1, 1, 8, 1, 1, 27, 27, 1, 1, 82, 240, 82, 1, 1, 245, 1700, 1700, 245, 1, 1, 732, 10571, 23586, 10571, 732, 1, 1, 2191, 60697, 259791, 259791, 60697, 2191, 1, 1, 6566, 331666, 2485398, 4675152, 2485398, 331666, 6566, 1, 1, 19689, 1756410, 21708138, 69413544, 69413544, 21708138, 1756410, 19689, 1
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OFFSET
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0,5
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LINKS
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FORMULA
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T(n, m) = T(n, n-m).
Sum_{k=0..n} T(n, k) = A000165(n) + 2*(2^n -(n+1)).
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EXAMPLE
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Rows n>=0 and columns 0<=m<=n start as:
1;
1, 1;
1, 8, 1;
1, 27, 27, 1;
1, 82, 240, 82, 1;
1, 245, 1700, 1700, 245, 1;
1, 732, 10571, 23586, 10571, 732, 1;
1, 2191, 60697, 259791, 259791, 60697, 2191, 1;
1, 6566, 331666, 2485398, 4675152, 2485398, 331666, 6566, 1;
1, 19689, 1756410, 21708138, 69413544, 69413544, 21708138, 1756410, 19689, 1;
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MATHEMATICA
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p[x_, n_] = (1 - x)^(n + 1)*Sum[(2*k + 1)^n*x^k, {k, 0, Infinity}];
f[n_, m_] := CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x][[m + 1]];
t[n_, m_] := f[n, m] + 2*Binomial[n, m] - 2 ;
Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
Flatten[%]
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PROG
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(Magma)
A060187:= func< n, k | (&+[(-1)^(k-j)*Binomial(n, k-j)*(2*j-1)^(n-1): j in [1..k]]) >;
(Sage)
def A060187(n, k): return sum( (-1)^(k-j)*binomial(n, k-j)*(2*j-1)^(n-1) for j in (1..k) )
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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Indices in definition corrected, row sum formula added by the Assoc. Eds. of the OEIS - Aug 20 2010
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STATUS
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approved
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