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A001242
Differences of reciprocals of unity.
(Formerly M5433 N2362)
7
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
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
KEYWORD
nonn,easy
EXTENSIONS
Formulae and more terms from Ralf Stephan, Feb 20 2005
STATUS
approved