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A000973
Fermat coefficients.
(Formerly M4976 N2137)
4
1, 15, 99, 429, 1430, 3978, 9690, 21318, 43263, 82225, 148005, 254475, 420732, 672452, 1043460, 1577532, 2330445, 3372291, 4790071, 6690585, 9203634, 12485550, 16723070, 22137570, 28989675, 37584261, 48275865, 61474519
OFFSET
8,2
COMMENTS
a(n) = A258708(n,n-8). - Reinhard Zumkeller, Jun 23 2015
REFERENCES
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
R. P. Loh, A. G. Shannon, A. F. Horadam, Divisibility Criteria and Sequence Generators Associated with Fermat Coefficients, Preprint, 1980.
P. A. Piza, Fermat coefficients, Math. Mag., 27 (1954), 141-146.
Simon Plouffe, Approximations de séries génératrices et quelques conjectures, Dissertation, Université du Québec à Montréal, 1992; arXiv:0911.4975 [math.NT], 2009.
Simon Plouffe, 1031 Generating Functions, Appendix to Thesis, Montreal, 1992
Index entries for linear recurrences with constant coefficients, signature (8, -28, 56, -70, 56, -28, 8, -1).
FORMULA
a(n) = binomial(2*n-8, 7)/8.
G.f.: (x^8)*(1+7*x+7*x^2+x^3)/(1-x)^8.
G.f.: A(x)= (1+7*x+7*x^2+x^3)/(x-1)^8 = 1 + 45*x/(G(0)-45*x), |x|<1; if |x|>1, G(0)=45*x;
G(k) = (k+1)*(2*k+3) + x*(k+5)*(2*k+9) - x*(k+1)*(k+6)*(2*k+3)*(2*k+11)/G(k+1); (continued fraction Euler's 1st kind, 1-step ). - Sergei N. Gladkovskii, Jun 15 2012
MAPLE
A000973:=(z+1)*(z**2+6*z+1)/(z-1)**8; # conjectured by Simon Plouffe in his 1992 dissertation
A000973:=n->binomial(2*n-8, 7)/8; seq(A000973(n), n=8..40); # Wesley Ivan Hurt, Apr 16 2014
MATHEMATICA
CoefficientList[Series[(1+7*x+7*x^2+x^3)/(1-x)^8, {x, 0, 40}], x] (* Vincenzo Librandi, Apr 10 2012 *)
PROG
(Magma) [Binomial(2*n-8, 7)/8: n in [8..40]]; // Vincenzo Librandi, Apr 10 2012
(Haskell)
a000973 n = a258708 n (n - 8) -- Reinhard Zumkeller, Jun 23 2015
CROSSREFS
Cf. A053129.
Cf. A258708.
Sequence in context: A174383 A341396 A307158 * A034266 A087661 A319777
KEYWORD
nonn,easy
EXTENSIONS
More terms from David W. Wilson, Oct 11 2000
STATUS
approved