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A258439
Powers of 3 alternating with powers of 2.
1
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
0,3
COMMENTS
a(n)*A098293(n) = A000400(floor(n/2)).
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
MAPLE
seq(op([3^n, 2^n]), n=0..20); # Muniru A Asiru, Jul 16 2018
MATHEMATICA
Flatten[Table[{3^n, 2^n}, {n, 0, 25}]] (* Vincenzo Librandi, Jul 17 2018 *)
PROG
(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
(GAP) Flat(List([0..20], n->[3^n, 2^n])); # Muniru A Asiru, Jul 16 2018
(Magma) &cat[[3^n, 2^n]: n in [0..35]]; // Vincenzo Librandi, Jul 17 2018
CROSSREFS
Sequence in context: A347365 A251555 A090880 * A346105 A188926 A193980
KEYWORD
nonn,easy,changed
AUTHOR
Luce ETIENNE, May 30 2015
STATUS
approved