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A111885
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Row sums of triangle A112492.
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2
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1, 2, 5, 20, 152, 2542, 100326, 10194844, 2809233510, 2212797607312, 5359196565766782, 39928779843430949176, 1018129474625651322506886, 85890171235256453902613870992, 26477529277143069417959927152215342
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = Sum_{j=0..n} A112492(n, j), n >= 0.
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MATHEMATICA
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T[n_, k_]:= T[n, k]= If[k==0 || k==n, 1, (k+1)^(n-k)*T[n-1, k-1] + k!*T[n-1, k]];
a[n_]:= a[n]= Sum[T[n, k], {k, 0, n}]; (* T = A112492 *)
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PROG
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(Magma)
T:= func< n, k | (-1)*Factorial(k+1)^(n-k)*(&+[(-1)^j*Binomial(k+1, j)/j^(n-k) : j in [1..k+1]]) >; // T = A112492
A111885:= func< n | (&+[T(n, k): k in [0..n]]) >;
(SageMath)
@CachedFunction
if (k==0 or k==n): return 1
else: return (k+1)^(n-k)*T(n-1, k-1) + factorial(k)*T(n-1, k)
def A111885(n): return sum(T(n, k) for k in range(n+1))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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