OFFSET
1,2
LINKS
Daniel Suteu, Table of n, a(n) for n = 1..10000
Daniel Suteu, Table of n, a(n) for n = 1..100000
EXAMPLE
For n=2, a(2) = 4 + a(1) = 5.
For n=3:
a(3) = 1 + a(8);
a(8) = 2*8 + a(8/2) = 16 + a(4);
a(4) = 2*4 + a(4/2) = 8 + a(2) = 13;
a(8) = 18+13 = 29;
a(3) = 1 + 29 = 30.
MAPLE
A266569 := proc(n)
option remember;
local k;
if n = 1 then
1;
elif type(n, 'even') then
2*n+procname(n/2) ;
else
k := (n-1)/2 ;
k+procname(4*k+4) ;
end if;
end proc:
seq(A266569(n), n=1..100) ; # R. J. Mathar, May 06 2016
MATHEMATICA
a[1] = 1; a[n_] := a[n] = If[EvenQ@ n, 2 n + a[n/2], (n - 1)/2 + a[2 (n + 1)]]; Array[a, 55] (* Michael De Vlieger, Jan 02 2016 *)
PROG
(Sidef)
func a((1)) { 1 }
func a(n {.is_even}) is cached { 2*n + a(n/2) }
func a(n {.is_odd }) is cached { (n-1)/2 + a(2*(n + 1)) }
1000.times { |n| say a(n) }
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Daniel Suteu, Jan 01 2016
STATUS
approved