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Let A={2,3,6,8,9,11,14,...} be the sequence of numbers k>=1 such that k+5 is odious (A000069). Let B be the complement of A. The sequence lists numbers for which the number of A-divisors equals the number of B-divisors.
1

%I #23 Jan 02 2023 12:30:49

%S 1,4,9,16,36,121,144,289,441,484,529,1156,1369,1600,1764,2025,2116,

%T 2209,3249,3481,4624,5041,5476,6241,6889,7056,7569,7921,8100,8464,

%U 8649,8836,11449,12321,12769,12996,13924,14641,15129,16641,20164,24336,24649,24964

%N Let A={2,3,6,8,9,11,14,...} be the sequence of numbers k>=1 such that k+5 is odious (A000069). Let B be the complement of A. The sequence lists numbers for which the number of A-divisors equals the number of B-divisors.

%C All terms are perfect squares.

%H Amiram Eldar, <a href="/A231180/b231180.txt">Table of n, a(n) for n = 1..10000</a>

%H Vladimir Shevelev, <a href="http://list.seqfan.eu/oldermail/seqfan/2013-October/011800.html">A set of sequences of perfect squares</a>

%e n=16 has 4 proper divisors {1,2,4,8} from which 2 from A {2,8} and 2 from B {1,4}. So 16 is in the sequence.

%t odiousQ[n_]:=OddQ[DigitCount[n,2][[1]]];

%t Select[Range[200],0==Length[#]-2Length[Select[#,odiousQ[#+5]&]]&[Most[Divisors[#^2]]]&]^2 (* _Peter J. C. Moses_, Nov 08 2013 *)

%Y Cf. A227891, A231175, A231176, A092498, A231178, A000005, A000069.

%K nonn,base

%O 1,2

%A _Vladimir Shevelev_ and _Peter J. C. Moses_, Nov 05 2013