A270814 -id:A270814 - cp's OEIS frontend

A266569 a(1) = 1; thereafter a(2k) = 4k + a(k); a(2k+1) = k + a(4k+4).

1, 5, 30, 13, 68, 42, 64, 29, 132, 88, 119, 66, 154, 92, 132, 61, 248, 168, 217, 128, 261, 163, 221, 114, 322, 206, 273, 148, 326, 192, 268, 125, 468, 316, 401, 240, 463, 293, 387, 208, 533, 345, 448, 251, 519, 313, 425, 210, 646, 422, 543, 310, 623, 381, 511

Offset: 1

Daniel Suteu, Jan 01 2016

			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.

Daniel Suteu, Table of n, a(n) for n = 1..10000
Daniel Suteu, Table of n, a(n) for n = 1..100000

Records (high water marks): A270811, A270812.

Cf. A270814, A271473, A271478, A271479.

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

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 *)

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) }

A271473 a(1)=0; thereafter a(2k)=k+a(k), a(2k+1)=k+a(6k+4).

Original entry on oeis.org

0, 1, 23, 3, 17, 26, 141, 7, 166, 22, 127, 32, 58, 148, 344, 15, 105, 175, 256, 32, 73, 138, 314, 44, 325, 71, 50699, 162, 218, 359, 50532, 31, 416, 122, 268, 193, 264, 275, 1166, 52, 50645, 94, 664, 160, 246, 337, 50470, 68, 399, 350, 561, 97, 198, 50726, 51137, 190, 821, 247, 1088, 389

Offset: 1

N. J. A. Sloane, Apr 08 2016

nonn

Inspired by A266569.

Robert Price, Table of n, a(n) for n = 1..1000

Cf. A266569, A270814.

A271473 := proc(n)
        local a, traj ;
        a := 0 ;
        traj := n ;
        while traj > 1 do
                if type(traj, 'even') then
                        a:=a+traj/2;
                        traj := traj/2 ;
                else
                        a:=a+(traj-1)/2;
                        traj := 3*traj+1 ;
                end if;
        end do:
        return a;
end proc:
[seq(A271473(n),n=1..60)];

a[1]=0; a[n_] := a[n] = If[EvenQ[n], n/2 + a[n/2], (n - 1)/2 + a[3*(n - 1) + 4]]; Array[a, 60] (* Robert Price, Apr 08 2016 *)

cp's OEIS Frontend

A266569 a(1) = 1; thereafter a(2k) = 4k + a(k); a(2k+1) = k + a(4k+4).

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