A258439 Powers of 3 alternating with powers of 2.
1, 1, 3, 2, 9, 4, 27, 8, 81, 16, 243, 32, 729, 64, 2187, 128, 6561, 256, 19683, 512, 59049, 1024, 177147, 2048, 531441, 4096, 1594323, 8192, 4782969, 16384, 14348907, 32768, 43046721, 65536, 129140163, 131072, 387420489, 262144, 1162261467
Offset: 0
Links
- Colin Barker, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature (0,5,0,-6).
Programs
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GAP
Flat(List([0..20],n->[3^n,2^n])); # Muniru A Asiru, Jul 16 2018
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Magma
&cat[[3^n, 2^n]: n in [0..35]]; // Vincenzo Librandi, Jul 17 2018
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Maple
seq(op([3^n,2^n]),n=0..20); # Muniru A Asiru, Jul 16 2018
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Mathematica
Flatten[Table[{3^n, 2^n}, {n, 0, 25}]] (* Vincenzo Librandi, Jul 17 2018 *) -
PARI
Vec(-(3*x^3+2*x^2-x-1)/((2*x^2-1)*(3*x^2-1)) + O(x^100)) \\ Colin Barker, May 30 2015
Formula
a(n) = ((5+(-1)^n)/2)^((2*n-1+(-1)^n)/4).
a(n) = 5*a(n-2)-6*a(n-4). - Colin Barker, May 30 2015
G.f.: -(3*x^3+2*x^2-x-1) / ((2*x^2-1)*(3*x^2-1)). - Colin Barker, May 30 2015
Comments