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A094419
Generalized ordered Bell numbers Bo(6,n).
18
1, 6, 78, 1518, 39390, 1277646, 49729758, 2258233998, 117196187550, 6842432930766, 443879517004638, 31674687990494478, 2465744921215207710, 207943837884583262286, 18885506918597311159518
OFFSET
0,2
COMMENTS
Sixth row of array A094416, which has more information.
LINKS
FORMULA
E.g.f.: 1/(7 - 6*exp(x)).
a(n) = Sum_{k=0..n} A131689(n,k)*6^k. - Philippe Deléham, Nov 03 2008
a(n) ~ n! / (7*(log(7/6))^(n+1)). - Vaclav Kotesovec, Mar 14 2014
a(0) = 1; a(n) = 6 * Sum_{k=1..n} binomial(n,k) * a(n-k). - Ilya Gutkovskiy, Jan 17 2020
a(0) = 1; a(n) = 6*a(n-1) - 7*Sum_{k=1..n-1} (-1)^k * binomial(n-1,k) * a(n-k). - Seiichi Manyama, Nov 17 2023
MATHEMATICA
t = 30; Range[0, t]! CoefficientList[Series[1/(7 - 6 Exp[x]), {x, 0, t}], x] (* Vincenzo Librandi, Mar 16 2014 *)
PROG
(Magma)
A094416:= func< n, k | (&+[Factorial(j)*n^j*StirlingSecond(k, j): j in [0..k]]) >;
A094419:= func< k | A094416(6, k) >;
[A094419(n): n in [0..30]]; // G. C. Greubel, Jan 12 2024
(SageMath)
def A094416(n, k): return sum(factorial(j)*n^j*stirling_number2(k, j) for j in range(k+1)) # array
def A094419(k): return A094416(6, k)
[A094419(n) for n in range(31)] # G. C. Greubel, Jan 12 2024
(PARI) my(N=25, x='x+O('x^N)); Vec(serlaplace(1/(7-6*exp(x)))) \\ Joerg Arndt, Jan 15 2024
KEYWORD
nonn
AUTHOR
Ralf Stephan, May 02 2004
STATUS
approved