A289992 - OEIS

%I #27 Oct 30 2023 10:29:59

%S 1,49,746,6122,34067,144963,506772,1524628,4074949,9898229,22220990,

%T 46695870,92769495,175610631,318756136,557659432,944355593,1553488697,

%U 2489980818,3898657938,5976186139,8985711691,13274641084,19296041660,27634190285

%N Number of magic labelings of the prism graph I X C_8 having magic sum n.

%H R. P. Stanley, <a href="/A002721/a002721.pdf">Examples of Magic Labelings</a>, Unpublished Notes, 1973 [Cached copy, with permission]

%F a(n) = A244880(n) + 2*Sum_{i=0..n-1} A244880(i).

%F Conjectures from _Colin Barker_, Sep 13 2017: (Start)

%F G.f.: (1 + x)*(1 + 6*x + x^2)*(1 + 32*x + 70*x^2 + 32*x^3 + x^4) / (1 - x)^10.

%F a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>9.

%F (End)

%Y Cf. A019298, A061927, A244497, A292281, A244873, A244880.

%K nonn

%O 0,2

%A _David J. Seal_, Sep 13 2017