A001242 Differences of reciprocals of unity. (Formerly M5433 N2362)

1, 274, 48076, 6998824, 929081776, 117550462624, 14500866102976, 1765130436471424, 213373597575314176, 25700650466807540224, 3089923562153380965376, 371145495540181143169024, 44558899569395347436056576, 5348360831598738338465357824

Offset

1,2

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

Colin Barker, Table of n, a(n) for n = 1..481

Mircea Merca, Some experiments with complete and elementary symmetric functions, Periodica Mathematica Hungarica, 69 (2014), 182-189.

Index entries for linear recurrences with constant coefficients, signature (274,-27000,1224000,-25920000,207360000).

Formula

G.f.: x / ((1-24*x)*(1-30*x)*(1-40*x)*(1-60*x)*(1-120*x)).

a(n) = (1/24) (24^n - 4*30^n + 6*40^n - 4*60^n + 120^n).

Prog

(PARI) Vec(1/(-207360000*x^5+25920000*x^4-1224000*x^3+27000*x^2-274*x+1) + O(x^100)) \\ Colin Barker, Apr 26 2015

Crossrefs

Equals 2^(n-1) * A103878(n).

Right-hand column 4 in triangle A008969.

Cf. a(n) = A112492(n+3, 5).

Sequence in context: A165677 A143076 A171346 * A214111 A344731 A023681

Adjacent sequences: A001239 A001240 A001241 * A001243 A001244 A001245

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

Formulae and more terms from Ralf Stephan, Feb 20 2005

Status

approved