OFFSET
0,1
COMMENTS
For n > 0, binary representation of a(n) is 1X11 where X is 2*n-1 zeros.
Number of conjugacy classes in Suzuki group Sz(2*4^n). - Eric M. Schmidt, Apr 18 2013
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..1000
Frank Luebeck, Numbers of Conjugacy Classes in Finite Groups of Lie Type.
Index entries for linear recurrences with constant coefficients, signature (5,-4).
FORMULA
G.f. ( 5-14*x ) / ( (1-4*x)*(1-x) ). - R. J. Mathar, Apr 09 2011
a(n) = +5*a(n-1) -4*a(n-2). [Joerg Arndt, Apr 09 2011]
a(n) = a(n-1)+6*4^(n-1) for n > 0, a(0)=5. - Felix P. Muga II, Mar 19 2014
a(n) = a(n-1)+12*a(n-2)-36 for n > 1, a(0)=5, a(1)=11. - Felix P. Muga II, Mar 19 2014
EXAMPLE
The first seven terms written in binary are 101, 1011, 100011, 10000011, 1000000011, 100000000011, and 10000000000011.
MATHEMATICA
2 4^Range[0, 30]+3 (* Harvey P. Dale, Apr 02 2011 *)
PROG
(Magma) [2*4^n+3: n in [1..100]]; // Vincenzo Librandi, Mar 29 2011
(Decimal BASIC)
FOR n=0 TO 1000
PRINT n; 2*4^n+3
NEXT n
END ! /* Bruno Berselli, Apr 28 2011 */
(PARI) a(n)=2*4^n+3 \\ Charles R Greathouse IV, Jul 02 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Brad Clardy, Mar 22 2011
STATUS
approved