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%I #23 Sep 08 2022 08:45:59
%S 12,25,77,319,1577,8575,48977,286759,1699817,10137775,60645377,
%T 363332599,2178384857,13065493375,78378545777,470228096839,
%U 2821239178697,16927047127375,101561119454177,609363227843479,3656168902513337,21936982025631775
%N a(n) = (2+3^n)*(3+2^n).
%H Bruno Berselli, <a href="/A195116/b195116.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (12,-47,72,-36).
%F G.f.: (12-119*x+341*x^2-294*x^3)/((1-x)*(1-2*x)*(1-3*x)*(1-6*x)).
%F Sum_{i=0..n} a(i) = (1/10)*(12*6^n+45*3^n+40*2^n+60*n+23).
%t Table[(2 + 3^n) (3 + 2^n), {n, 0, 30}] (* _Vincenzo Librandi_, Mar 26 2013 *)
%o (Magma) [(2+3^n)*(3+2^n): n in [0..21]];
%o (PARI) for(n=0, 21, print1((2+3^n)*(3+2^n)", "));
%o (Python)
%o def a(n): return (2+3**n)*(3+2**n)
%o print([a(n) for n in range(23)]) # _Michael S. Branicky_, Dec 25 2021
%Y Cf. A060013 ((1+2^n)*(2+1) with n>3).
%Y Cf. A021029 (for the recurrence).
%K nonn,easy
%O 0,1
%A _Bruno Berselli_, Sep 09 2011
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