A373730 - OEIS

%I #31 Aug 19 2024 11:42:30

%S 1,11,5,29,19,47,7,65,37,83,23,101,55,119,1,137,73,155,41,173,91,191,

%T 25,209,109,227,59,245,127,263,17,281,145,299,77,317,163,335,43,353,

%U 181,371,95,389,199,407,13,425,217,443,113,461,235,479,61,497,253,515

%N Reduced Collatz function R applied to the numbers 6n+1: a(n) = R(6n+1), where R(k) = (3k+1)/2^r, with r as large as possible.

%H Paolo Xausa, <a href="/A373730/b373730.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = A000265(A017185(n)).

%t A373730[n_] := #/2^IntegerExponent[#, 2] & [9*n + 2];

%t Array[A373730, 100, 0] (* _Paolo Xausa_, Aug 19 2024 *)

%o (PARI) a(n) = n=9*n+2; n>>valuation(n,2);

%Y Cf. A000265, A017185, A075677, A260658.

%K nonn,easy

%O 0,2

%A _Jonas Kaiser_, Jun 17 2024