A137344 a(n)=4a(n-2). Also 3*A084221.

3, 9, 12, 36, 48, 144, 192, 576, 768, 2304, 3072, 9216, 12288, 36864, 49152, 147456, 196608, 589824, 786432, 2359296, 3145728, 9437184, 12582912, 37748736, 50331648, 150994944, 201326592, 603979776, 805306368, 2415919104

Offset: 0

Author

Paul Curtz, Apr 21 2008

Keywords

• nonn

Links

• Index entries for linear recurrences with constant coefficients, signature (0, 4).

Programs

Mathematica

RecurrenceTable[{a[1]==3,a[2]==9,a[n]==4*a[n-2]},a,{n,30}] (* or *) LinearRecurrence[ {0,4},{3,9},30] (* Harvey P. Dale, Sep 20 2018 *)

Extensions

More terms from Harvey P. Dale, Sep 20 2018