A001237
Differences of reciprocals of unity.
Original entry on oeis.org
31, 3661, 1217776, 929081776, 1413470290176, 3878864920694016, 17810567950611972096, 129089983180418186674176, 1409795030885143760732160000, 22335321387514981111936450560000, 497400843208278958640564703068160000, 15161356456130244705175927906904309760000
Offset: 1
- F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied Tables, Cambridge, 1966, p. 228.
- N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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a[n_] := -(Factorial[n + 1]^4)*Sum[(-1)^k Binomial[n + 1, k]/k^4, {k, 1, n + 1}];Table[a[n],{n,14}] (* James C. McMahon, Dec 12 2023 *)
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a(n)=-(n+1)!^4*sum(k=1,n+1,(-1)^k*binomial(n+1,k)/k^4) \\ Charles R Greathouse IV, Mar 29 2012
A111887
Seventh column of triangle A112492 (inverse scaled Pochhammer symbols).
Original entry on oeis.org
1, 13068, 104587344, 673781602752, 3878864920694016, 21006340945438768128, 110019668725577574273024, 565858042127972959667208192, 2882220940619488483325345857536, 14605752814655604919042956624396288
Offset: 0
Also right-hand column 6 in triangle
A008969.
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A111887:= func< n | (-1)*Factorial(7)^n*(&+[(-1)^j*Binomial(7,j)/j^n : j in [1..7]]) >;
[A111887(n): n in [0..30]]; // G. C. Greubel, Jul 24 2023
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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]]; (* T = A112492 *)
Table[T[n+6,6], {n,0,30}] (* G. C. Greubel, Jul 24 2023 *)
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a(n) = -((7!)^n)*sum(j=1, 7, ((-1)^j)*binomial(7, j)/j^n); \\ Michel Marcus, Apr 28 2020
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@CachedFunction
def T(n,k): # T = A112492
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 A111887(n): return T(n+6,6)
[A111887(n) for n in range(31)] # G. C. Greubel, Jul 24 2023
A111888
Eighth column of triangle A112492 (inverse scaled Pochhammer symbols).
Original entry on oeis.org
1, 109584, 7245893376, 381495483224064, 17810567950611972096, 778101042571221893382144, 32762625292956765972873609216, 1351813956241264848815287984717824
Offset: 0
Also right-hand column 7 in triangle
A008969.
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A111888:= func< n | (-1)*Factorial(8)^n*(&+[(-1)^j*Binomial(8,j)/j^n : j in [1..8]]) >;
[A111888(n): n in [0..30]]; // G. C. Greubel, Jul 24 2023
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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]]; (* T = A112492 *)
Table[T[n+7,7], {n,0,30}] (* G. C. Greubel, Jul 24 2023 *)
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a(n) = -((8!)^n)*sum(j=1, 8, ((-1)^j)*binomial(8, j)/j^n); \\ Michel Marcus, Apr 28 2020
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@CachedFunction
def T(n,k): # T = A112492
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 A111888(n): return T(n+7,7)
[A111888(n) for n in range(31)] # G. C. Greubel, Jul 24 2023
A103879
Square array T(n,k) read by antidiagonals: numerators of Stirling numbers of first kind with negative argument S1(-n,k), n,k>=0.
Original entry on oeis.org
1, 1, 0, 1, -1, 0, 1, -3, 1, 0, 1, -11, 7, -1, 0, 1, -25, 85, -15, 1, 0, 1, -137, 415, -575, 31, -1, 0, 1, -49, 12019, -5845, 3661, -63, 1, 0, 1, -121, 13489, -874853, 76111, -22631, 127, -1, 0, 1, -761, 726301, -336581, 58067611, -952525, 137845, -255, 1
Offset: 0
1, 0, 0, 0, 0, 0,
1, -1, 1, -1, 1, -1,
1/2, -3/4, 7/8, -15/16, 31/32, -63/64,
1/6, -11/36, 85/216, -575/1296, 3661/7776, -22631/46656,
1/24,-25/288,415/3456,-5845/41472,76111/497664,-952525/5971968,
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T(n,k)=numerator(1/n!*polcoeff(Ser(1/prod(i=1,n,1+x/i)),k))
A103880
Square array T(n,k) read by antidiagonals: denominators of Stirling numbers of first kind with negative argument S1(-n,k), n,k>=0.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 6, 4, 1, 1, 24, 36, 8, 1, 1, 120, 288, 216, 16, 1, 1, 720, 7200, 3456, 1296, 32, 1, 1, 5040, 14400, 432000, 41472, 7776, 64, 1, 1, 40320, 235200, 2592000, 25920000, 497664, 46656, 128, 1, 1, 362880, 11289600, 889056000, 51840000
Offset: 0
1, 0, 0, 0, 0, 0,
1, -1, 1, -1, 1, -1,
1/2, -3/4, 7/8, -15/16, 31/32, -63/64,
1/6, -11/36, 85/216, -575/1296, 3661/7776, -22631/46656,
1/24,-25/288,415/3456,-5845/41472,76111/497664,-952525/5971968,
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T(n,k)=denominator(1/n!*polcoeff(Ser(1/prod(i=1,n,1+x/i)),k))
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