A003272 - OEIS

%I #20 Sep 08 2022 08:44:32

%S 0,-24,240,-504,480,-264,95,-24,5,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,

%T 0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,

%U 0,1,0,1,0,1,0,1,0,1,0,1,0,1,0

%N a(n) = ceiling((-4n)/Bernoulli(2n)).

%D Douglas C. Ravenel, Complex cobordism theory for number theorists, Lecture Notes in Mathematics, 1326, Springer-Verlag, Berlin-New York, 1988, pp. 123-133.

%D F. Hirzebruch et al., Manifolds and Modular Forms, Vieweg, 2nd ed. 1994, p. 130.

%H G. C. Greubel, <a href="/A003272/b003272.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Be#Bernoulli">Index entries for sequences related to Bernoulli numbers.</a>

%t Table[Ceiling[(-4n)/BernoulliB[2n]], {n, 0, 75}] (* _Alonso del Arte_, Jul 19 2012 *)

%o (PARI) vector(75, n, n--; ceil(-4*n/bernfrac(2*n))) \\ _G. C. Greubel_, Jul 04 2019

%o (Magma) [Ceiling(-4*n/Bernoulli(2*n)): n in [0..75]]; // _G. C. Greubel_, Jul 04 2019

%o (Sage) [ceil(-4*n/bernoulli(2*n)) for n in (0..75)] # _G. C. Greubel_, Jul 04 2019

%K sign

%O 0,2

%A _N. J. A. Sloane_