A193475 - OEIS

%I #10 Jun 30 2023 18:44:55

%S 2,56,992,16256,261632,4192256,67100672,1073709056,17179738112,

%T 274877382656,4398044413952,70368735789056,1125899873288192,

%U 18014398375264256,288230375614840832,4611686016279904256,73786976286248271872,1180591620683051565056

%N a(n) = 4*16^n - 2*4^n.

%H Peter Luschny, <a href="http://oeis.org/wiki/User:Peter_Luschny/TheLostBernoulliNumbers">The lost Bernoulli numbers.</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (20, -64).

%F Recurrence: a(0) = 2, a(1) = 56, a(n) = 20*a(n-1) - 64*a(n-2).

%F G.f.: (16*x+2)/(64*x^2-20*x+1).

%F E.g.f.: 4*exp(16*x) - 2*exp(4*x).

%p A193475 := proc(n) 2^(2*n+1); %^2; % - %% end: seq (A193475(n), n=0..20);

%K nonn

%O 0,1

%A Peter Luschny, Aug 07 2011