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A178122
Triangle T(n,m) = A060187(n+1,m+1) + 2*binomial(n,m) - 2, read by rows.
1
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
OFFSET
0,5
FORMULA
T(n, m) = A060187(n+1,m+1) + 2*A007318(n,m) - 2.
T(n, m) = T(n, n-m).
Sum_{k=0..n} T(n, k) = A000165(n) + 2*(2^n -(n+1)).
EXAMPLE
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;
MATHEMATICA
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[%]
PROG
(Magma)
A060187:= func< n, k | (&+[(-1)^(k-j)*Binomial(n, k-j)*(2*j-1)^(n-1): j in [1..k]]) >;
A178122:= func< n, k | A060187(n+1, k+1) + 2*Binomial(n, k) - 2 >;
[A178122(n, k): k in [0..n], n in [0..12]]; // G. C. Greubel, Mar 18 2022
(Sage)
def A060187(n, k): return sum( (-1)^(k-j)*binomial(n, k-j)*(2*j-1)^(n-1) for j in (1..k) )
def A178122(n, k): return A060187(n+1, k+1) + 2*binomial(n, k) - 2
flatten([[A178122(n, k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 18 2022
CROSSREFS
KEYWORD
nonn,tabl,easy
AUTHOR
Roger L. Bagula, May 20 2010
EXTENSIONS
Indices in definition corrected, row sum formula added by the Assoc. Eds. of the OEIS - Aug 20 2010
STATUS
approved