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%I
%S 7,30,124,504,2032,8160,32704,130944,524032,2096640,8387584,33552384,
%T 134213632,536862720,2147467264,8589901824,34359672832,137438822400,
%U 549755551744,2199022731264,8796091973632,35184369991680
%N a(n) = 6*a(n-1)-8*a(n-2) for n > 1; a(0) = 7, a(1) = 30.
%C Related to Reverse and Add trajectory of 22 in base 2: A061561(4*n+2) = 12*a(n).
%C Third binomial transform of A010729.
%H Vincenzo Librandi, <a href="/A171472/b171472.txt">Table of n, a(n) for n = 0..500</a>
%F a(n) = 8*4^n-2^n.
%F G.f.: 12*(7-12*x)/((1-2*x)*(1-4*x)).
%o (PARI) {m=22; v=concat([7, 30], vector(m-2)); for(n=3, m, v[n]=6*v[n-1]-8*v[n-2]); v}
%o (MAGMA) [8*4^n-2^n: n in [0..30]]; // Vincenzo Librandi, May 31 2011
%Y Cf. A061561, A010729 (repeat 7, 9), A171470, A171471, A171473.
%K nonn
%O 0,1
%A _Klaus Brockhaus_, Dec 09 2009
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