OFFSET
0,1
LINKS
Ivan Neretin, Table of n, a(n) for n = 0..10000
R. Stephan, Some divide-and-conquer sequences ...
R. Stephan, Table of generating functions
FORMULA
For n>0, a(n)=b(n) with b(0)=0, b(2n) = -b(n)+9n+3, b(2n+1) = -b(n)+9n+6-2[n==0]. - Ralf Stephan, Oct 23 2003
MATHEMATICA
Fold[Append[#1, Plus @@ Complement[Range[Max@#1 + 3], #1][[{#2 + 1, #2 + 2}]]] &, {2, 4}, Range[44]] (* Ivan Neretin, Mar 30 2017 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved