OFFSET
0,4
LINKS
Michel Marcus, Table of n, a(n) for n = 0..100
FORMULA
a(2n+2) = 4*a(2n)+A000034(n).
a(2n+1) = 2*a(2n).
MATHEMATICA
a[ n_] := If[n < 2, 0, 2 a[n - 1] + If[ EvenQ[n], Mod[n/2, 2, 1], 0]]; (* Michael Somos, Mar 02 2014 *)
PROG
(PARI) f(n) = 2^n+3*(-1)^n; \\ A140657
a(n) = f(n+2)\10; \\ Michel Marcus, Sep 08 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul Curtz, Jul 10 2008
EXTENSIONS
Edited and extended by R. J. Mathar, Jul 29 2008
Name corrected by Michel Marcus, Sep 08 2019
STATUS
approved