This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A325572 #7 May 11 2019 02:24:25 %S A325572 2,4,6,8,9,10,12,14,16,18,20,21,22,24,26,28,30,32,33,34,35,36,38,40, %T A325572 42,44,45,46,48,49,50,52,54,56,58,60,62,64,65,66,68,70,72,74,75,76,78, %U A325572 80,82,84,86,88,90,92,93,94,96,98,100,102,104,105,106,108,110,112,114,116,118,120,122,124,126,128,129,130,132,133 %N A325572 Numbers n that have divisor d > 1 such that A048720(A065621(d),n/d) = n. %C A325572 Equally, numbers n such that there exists natural numbers t > 1 and u >= 1, for which A048720(t,u) = n and A065620(t)*u = n. %H A325572 Antti Karttunen, <a href="/A325572/b325572.txt">Table of n, a(n) for n = 1..10000</a> %o A325572 (PARI) %o A325572 A048720(b,c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2); %o A325572 A065621(n) = bitxor(n-1,n+n-1); %o A325572 isA325572(n) = fordiv(n,d,if(A048720(A065621(n/d),d)==n,return(d<n))); %Y A325572 Cf. A048720, A065620, A065621, A325570 (complement). %Y A325572 Union of A005843 (without zero) and A325573 (odd terms). %K A325572 nonn %O A325572 1,1 %A A325572 _Antti Karttunen_, May 10 2019