login
Row sums of triangle A112492.
2

%I #9 Jul 25 2023 09:15:05

%S 1,2,5,20,152,2542,100326,10194844,2809233510,2212797607312,

%T 5359196565766782,39928779843430949176,1018129474625651322506886,

%U 85890171235256453902613870992,26477529277143069417959927152215342

%N Row sums of triangle A112492.

%H G. C. Greubel, <a href="/A111885/b111885.txt">Table of n, a(n) for n = 0..55</a>

%F a(n) = Sum_{j=0..n} A112492(n, j), n >= 0.

%t 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]];

%t a[n_]:= a[n]= Sum[T[n,k], {k,0,n}]; (* T = A112492 *)

%t Table[a[n], {n,0,40}] (* _G. C. Greubel_, Jul 24 2023 *)

%o (Magma)

%o 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

%o A111885:= func< n | (&+[T(n,k): k in [0..n]]) >;

%o [A111885(n): n in [0..40]]; // _G. C. Greubel_, Jul 24 2023

%o (SageMath)

%o @CachedFunction

%o def T(n,k): # T = A112492

%o if (k==0 or k==n): return 1

%o else: return (k+1)^(n-k)*T(n-1,k-1) + factorial(k)*T(n-1,k)

%o def A111885(n): return sum(T(n,k) for k in range(n+1))

%o [A111885(n) for n in range(31)] # _G. C. Greubel_, Jul 24 2023

%Y Cf. A112492.

%K nonn,easy

%O 0,2

%A _Wolfdieter Lang_, Sep 12 2005