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A001237
Differences of reciprocals of unity.
(Formerly M5229 N2276)
2
31, 3661, 1217776, 929081776, 1413470290176, 3878864920694016, 17810567950611972096, 129089983180418186674176, 1409795030885143760732160000, 22335321387514981111936450560000, 497400843208278958640564703068160000, 15161356456130244705175927906904309760000
OFFSET
1,1
REFERENCES
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).
LINKS
Mircea Merca, Some experiments with complete and elementary symmetric functions, Periodica Mathematica Hungarica, 69 (2014), 182-189.
FORMULA
a(n) = (n + 1)!^4/480*(20*Psi(n + 2)^4 + 80*gamma*Psi(n + 2)^3 - 120*Psi(n + 2)^2*Psi(1, n + 2) + 20*Pi^2*Psi(n + 2)^2 + 120*gamma^2*Psi(n + 2)^2 - 240*gamma*Psi(n + 2)*Psi(1, n + 2) + 80*Psi(n + 2)*Psi(2, n + 2) + 60*Psi(1, n + 2)^2 + 40*gamma*Pi^2*Psi(n + 2) + 160*Zeta(3)*Psi(n + 2) + 80*gamma^3*Psi(n + 2) - 20*Pi^2*Psi(1, n + 2) - 120*gamma^2*Psi(1, n + 2) + 80*gamma*Psi(2, n + 2) - 20*Psi(3, n + 2) + 160*gamma*Zeta(3) + 3*Pi^4 + 20*gamma^4 + 20*gamma^2*Pi^2). - Vladeta Jovovic, Aug 10 2002
a(n) = (n+1)!^4 * Sum_{i=1..n+1} Sum_{j=1..i} Sum_{k=1..j} Sum_{l=1..k} 1/(ijkl).
a(n) = (n+1)!^4 * Sum_{k=1..n+1} (-1)^(k+1)*C(n+1,k)/k^4. - Sean A. Irvine, Mar 29 2012
MATHEMATICA
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 *)
PROG
(PARI) 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
CROSSREFS
Column 4 in triangle A008969.
Sequence in context: A218661 A183783 A072913 * A289397 A177465 A187755
KEYWORD
nonn
EXTENSIONS
More terms from Vladeta Jovovic, Aug 10 2002
a(11)-a(12) from James C. McMahon, Dec 12 2023
STATUS
approved