A086652 a(n) = A000225(n+3)-A052955(n).

6, 13, 28, 58, 120, 244, 496, 1000, 2016, 4048, 8128, 16288, 32640, 65344, 130816, 261760, 523776, 1047808, 2096128, 4192768, 8386560, 16774144, 33550336, 67102720, 134209536, 268423168, 536854528, 1073717248, 2147450880

Offset: 0

Author

Marco Matosic, Jul 27 2003

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (2,2,-4).

Crossrefs

Cf. A000225, A052955, A055010, A086221.

Programs

Maple

f:=n->2^(n+3)-((5-(-1)^n)/2)*2^((2*n-1+(-1)^n)/4);

Formula

a(2n) = A006516(n+2); a(2n+1) = A086221(n+1).

G.f.: ( 6+x-10*x^2 ) / ( (2*x-1)*(2*x^2-1) ). - R. J. Mathar, Sep 15 2012

a(n) = 2^(n+3)-((5-(-1)^n)/2)*2^((2*n-1+(-1)^n)/4). - Luce ETIENNE, Sep 23 2014

Extensions

Edited and extended by David Wasserman, Feb 17 2005