[seqfan] Definition of A0033053

[israel at math.ubc.ca]

A0033053 is titled "Numbers n such that base 2 representation Sum{d(i)*2^i: 
i=0,1,...,m} has odd d(i) for all odd i." However, it seems to me that the 
listed entries 1, 3, 6, 7, 13, 15, 26, 27, 30, 31, 53, 55, 61, 63, 106, 
107, 110, 111, 122, 123, 126, 127, 213, 215, 221, 223, 245, 247, 253, 255, 
426, 427, 430, 431, 442, 443, 446, 447, 490, 491, 494, 495, 506, 507, 510, 
511, 853, 855, 861, 863 are those for which d(i) = 1 when i+m is odd, not 
when i is odd. For example,
   26 = 11010_2 (m=4, d(i) = 1 for i=1 and 3)
but
   53 = 110101_2 (m=5, d(i) = 1 for i=0,2 and 4)

Robert Israel
University of British Columbia and D-Wave Systems