|
%I #20 Feb 12 2018 11:19:43
%S 1,4,12,24,39,59,84,112,143,179,220,264,311,363,420,480,543,611,684,
%T 760,839,923,1012,1104,1199,1299,1404,1512,1623,1739,1860,1984,2111,
%U 2243,2380,2520,2663,2811,2964,3120,3279,3443,3612,3784,3959,4139,4324,4512
%N Partial sums of A296368.
%H Rémy Sigrist, <a href="/A296909/b296909.txt">Table of n, a(n) for n = 0..1000</a>
%H Reticular Chemistry Structure Resource (RCSR), <a href="http://rcsr.net/layers/mcm">The mcm tiling (or net)</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (3,-4,4,-3,1).
%F From _Colin Barker_, Dec 23 2017: (Start)
%F G.f.: (1 + x + 4*x^2 + 2*x^4 + x^5 - x^6) / ((1 - x)^3*(1 + x^2)).
%F a(n) = (-1/4-i/4)*((1-i) + (-i)^n - i*i^n) + 2*n + 2*n^2 for n>1, where i=sqrt(-1).
%F a(n) = 3*a(n-1) - 4*a(n-2) + 4*a(n-3) - 3*a(n-4) + a(n-5) for n>6.
%F (End)
%o (PARI) Vec((1 + x + 4*x^2 + 2*x^4 + x^5 - x^6) / ((1 - x)^3*(1 + x^2)) + O(x^50)) \\ _Colin Barker_, Dec 24 2017
%Y Cf. A296368.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Dec 22 2017
%E Terms a(8)-a(20) and RCSR link from _Davide M. Proserpio_, Dec 22 2017
%E More terms from _Rémy Sigrist_, Dec 23 2017
|
