cp's OEIS Frontend

A280506 Nonpalindromic part of n in base 2 (with carryless GF(2)[X] factorization): a(n) = A280500(n,A280505(n)).

%I A280506 #20 May 13 2018 20:42:54
%S A280506 1,1,1,1,1,1,1,1,1,1,11,1,13,1,1,1,1,1,19,1,1,11,13,1,25,13,1,1,11,1,
%T A280506 1,1,1,1,13,1,37,19,11,1,41,1,25,11,1,13,47,1,11,25,1,13,19,1,55,1,13,
%U A280506 11,59,1,61,1,1,1,1,1,67,1,69,13,61,1,1,37,13,19,59,11,25,1,81,41,11,1,1,25,87,11,55,1,91,13,1,47,19,1,97,11,1,25,13,1,103
%N A280506 Nonpalindromic part of n in base 2 (with carryless GF(2)[X] factorization): a(n) = A280500(n,A280505(n)).
%C A280506 a(n) = number obtained when the maximal base-2 palindromic divisor of n, A280505(n), is divided out of n with carryless GF(2)[X] factorization (see examples of A280500 for the explanation).
%C A280506 Apart from 1, all terms are present in A164861 (form their proper subset).
%H A280506 Antti Karttunen, <a href="/A280506/b280506.txt">Table of n, a(n) for n = 1..8192</a>
%H A280506 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A280506 <a href="/index/Ge#GF2X">Index entries for sequences operating on polynomials in ring GF(2)[X]</a>
%F A280506 a(n) = A280500(n,A280505(n)).
%F A280506 Other identities. For all n >= 1:
%F A280506 a(2n) = a(A000265(n)) = a(n).
%F A280506 A048720(a(n), A280505(n)) = n.
%o A280506 (Scheme) (define (A280506 n) (A280500bi n (A280505 n))) ;; Code for A280500bi given in A280500.
%Y A280506 Cf. A000265, A048720, A057889, A057891, A164861, A280500, A280502, A280504, A280508, A280509.
%Y A280506 Cf. A057890 (positions of ones).
%K A280506 nonn,base
%O A280506 1,11
%A A280506 _Antti Karttunen_, Jan 09 2017
%E A280506 Erroneous claim removed from comments by _Antti Karttunen_, May 13 2018