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A361875 Integers of the form k*2^m + 1 where 0 < k <= m and k is odd.

%I A361875 #9 Mar 28 2023 03:46:59
%S A361875 3,5,9,17,25,33,49,65,97,129,161,193,257,321,385,513,641,769,897,1025,
%T A361875 1281,1537,1793,2049,2561,3073,3585,4097,4609,5121,6145,7169,8193,
%U A361875 9217,10241,12289,14337,16385,18433,20481,22529,24577,28673,32769,36865,40961,45057,49153,57345,65537,73729,81921
%N A361875 Integers of the form k*2^m + 1 where 0 < k <= m and k is odd.
%C A361875 Every term is odd.
%e A361875 641 = 5*2^7 + 1 is a term because 0 < 5 <= 7 and 5 is odd.
%p A361875 # Maple program (due to _David A. Corneth_)
%p A361875 aList := proc(upto)
%p A361875    local i, j, R:
%p A361875    R := {}:
%p A361875    for i from 1 to ilog2(upto) do
%p A361875       for j from 1 to min(i, floor(upto/2^i)) do
%p A361875          R := `union`(R, {j*2^i+1}): od: od:
%p A361875    R: end:
%p A361875 aList(10^12);
%Y A361875 Cf. A361180 (prime terms).
%K A361875 nonn,easy
%O A361875 1,1
%A A361875 _Lorenzo Sauras Altuzarra_, Mar 27 2023