A348074 a(n) = A035327(n) if n is even, 3n + 1 if n is odd.

1, 4, 1, 10, 3, 16, 1, 22, 7, 28, 5, 34, 3, 40, 1, 46, 15, 52, 13, 58, 11, 64, 9, 70, 7, 76, 5, 82, 3, 88, 1, 94, 31, 100, 29, 106, 27, 112, 25, 118, 23, 124, 21, 130, 19, 136, 17, 142, 15, 148, 13, 154, 11, 160, 9, 166, 7, 172, 5, 178, 3, 184, 1, 190, 63

Offset

0,2

Links

Table of n, a(n) for n=0..64.

Example

n    parity   function       a(n)
=    =====    =========     ======
0     even    A035327(0)      1
1     odd      3*1 + 1        4
2     even    A035327(2)      1
3     odd      3*3 + 1       10
4     even    A035327(4)      3
5     odd      3*5 + 1       16

Prog

(Python)
def A348074(n):
    if n%2==0:
        if n==0: return 1
        else: return (1<<int.bit_length(n)) - n - 1 #A035327(n)
    else: return 3*n+1
(Python)
def A348074(n): return 3*n+1 if n&1 or n==0 else (~n)^(-1<<n.bit_length()) # Chai Wah Wu, Dec 20 2022

Crossrefs

Cf. A006370, A035327.

Sequence in context: A262370 A108759 A158824 * A334161 A039806 A030320

Adjacent sequences: A348071 A348072 A348073 * A348075 A348076 A348077

Keyword

nonn

Author

Alexander Van Plantinga, Sep 27 2021

Status

approved