%I #15 Sep 08 2022 08:45:13

%S 1,67,1993,43891,836521,14764627,249723433,4123297651,67157947561,

%T 1085384064787,17464790421673,280328391247411,4493290901135401,

%U 71964955947764947,1152089156508284713,18439265231953981171,295080697103288816041,4721762414918959913107

%N Number of connected relations.

%H G. C. Greubel, <a href="/A092795/b092795.txt">Table of n, a(n) for n = 1..825</a>

%H G. Kilibarda and V. Jovovic, <a href="https://arxiv.org/abs/1411.4187">Enumeration of some classes of T_0-hypergraphs</a>, arXiv:1411.4187 [math.CO], 2014.

%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (43,-701,5477,-20658,30240).

%F a(n) = 16^n - 4*9^n - 3*7^n + 12*6^n - 6*5^n.

%F G.f.: x*(318*x^3+187*x^2-24*x-1) / ((5*x-1)*(6*x-1)*(7*x-1)*(9*x-1)*(16*x-1)). - _Colin Barker_, Jul 13 2013

%t Table[16^n - 4*9^n - 3*7^n + 12*6^n - 6*5^n, {n, 1, 50}] (* _G. C. Greubel_, Oct 08 2017 *)

%o (PARI) for(n=1,50, print1(16^n - 4*9^n - 3*7^n + 12*6^n - 6*5^n, ", ")) \\ _G. C. Greubel_, Oct 08 2017

%o (Magma) [16^n - 4*9^n - 3*7^n + 12*6^n - 6*5^n: n in [1..50]]; // _G. C. Greubel_, Oct 08 2017

%Y Cf. A005333, A001047, A002501, A002502, A093732, A093733.

%K nonn,easy

%O 1,2

%A Goran Kilibarda, _Vladeta Jovovic_, Apr 15 2004

%E More terms from _Colin Barker_, Jul 13 2013