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%I #13 Jun 02 2018 13:09:09
%S 1,3,5,7,9,15,17,21,25,27,31,33,35,45,49,51,63,65,73,75,81,85,93,99,
%T 105,107,119,125,127,129,135,147,153,155,165,175,189,195,217,219,225,
%U 231,243,245,255,257,273,279,289,297,313,315,321,325,341,343,357,365
%N Positive numbers that can be expressed as the product of 1 or more binary palindromes (elements of A006995).
%H Robert Israel, <a href="/A305409/b305409.txt">Table of n, a(n) for n = 1..3086</a>
%e 155 is in the sequence because it is 5*31, and both 5 and 31 are palindromic numbers (with binary representations 101 and 11111, respectively).
%p dmax:= 10: N:= 2^dmax: # to get all terms < N
%p revdigs:= proc(n)
%p local L, Ln, i;
%p L:= convert(n, base, 2);
%p Ln:= nops(L);
%p add(L[i]*2^(Ln-i), i=1..Ln);
%p end proc:
%p A:= {}:
%p for d from 2 to dmax do
%p if d::even then
%p A:= A union {seq(2^(d/2)*x + revdigs(x), x=2^(d/2-1)..2^(d/2)-1)}
%p else
%p m:= (d-1)/2;
%p B:={seq(2^(m+1)*x + revdigs(x), x=2^(m-1)..2^m-1)};
%p A:= A union B union map(`+`, B, 2^m)
%p fi
%p od:
%p R:= {1}:
%p for b in A do
%p R:= map(t -> seq(t*b^j,j=0..floor(log[b](N/t))), R)
%p od:
%p sort(convert(R,list)); # _Robert Israel_, Jun 01 2018
%Y Cf. A006995.
%K nonn,base
%O 1,2
%A _Jeffrey Shallit_, May 31 2018
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