A201636 Triangle read by rows, n>=0, k>=0, T(0,0) = 1, T(n,k) = Sum_{j=0..k} (C(n+k,k-j)*(-1)^(k-j)*2^(n-j)*Sum_{i=0..j} (C(n+j,i)*|S(n+j-i,j-i)|)), S = Stirling number of first kind.
1, 0, 1, 0, 4, 3, 0, 24, 40, 15, 0, 192, 520, 420, 105, 0, 1920, 7392, 9520, 5040, 945, 0, 23040, 116928, 211456, 176400, 69300, 10395, 0, 322560, 2055168, 4858560, 5642560, 3465000, 1081080, 135135, 0, 5160960, 39896064, 117722880, 177580480, 150870720, 73153080, 18918900, 2027025
Offset: 0
Examples
[n\k 0, 1, 2, 3, 4, 5] [0] 1, [1] 0, 1, [2] 0, 4, 3, [3] 0, 24, 40, 15, [4] 0, 192, 520, 420, 105, [5] 0, 1920, 7392, 9520, 5040, 945,
Programs
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Maple
A201636 := proc(n,k) if n=0 and k=0 then 1 else add(binomial(n+k,k-j)*(-1)^(n+k-j)*2^(n-j)* add(binomial(n+j,i)*stirling1(n+j-i,j-i),i=0..j),j=0..k) fi end: for n from 0 to 8 do print(seq(A201636(n,k),k=0..n)) od;
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Mathematica
T[0, 0] = 1; T[n_, k_] := T[n, k] = Sum[Binomial[n+k, k-j]*(-1)^(n+k-j)* 2^(n-j)*Sum[Binomial[n+j, i]*StirlingS1[n+j-i, j-i], {i, 0, j}], {j, 0, k}]; Table[T[n, k], {n, 0, 8}, {k, 0, n}] (* Jean-François Alcover, Jun 29 2019 *)
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Sage
def A201636(n,k) : if n==0 and k==0: return 1 return add(binomial(n+k,k-j)*(-1)^(k-j)*2^(n-j)*add(binomial(n+j,i)* stirling_number1(n+j-i,j-i) for i in (0..j)) for j in (0..k))
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