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 A075799 #16 Mar 10 2025 09:42:13 %S A075799 1,6,22,33,55,77,111,141,161,202,262,303,323,393,454,505,515,535,545, %T A075799 565,626,707,717,737,767,818,838,858,878,898,939,949,959,979,989,1111, %U A075799 1441,1661,1991,2002,2442,3003,3113,3223,3443,3883,4774,5005,5115,6666,7117,7447 %N A075799 Palindromic numbers which are products of an even number of distinct primes. %H A075799 Paolo Xausa, <a href="/A075799/b075799.txt">Table of n, a(n) for n = 1..1000</a> %e A075799 1, 111=3*37 and 858=2*3*11*13 are palindromic and products of an even number of distinct primes. %p A075799 test := proc(n) local d; d := convert(n,base,10); return ListTools[Reverse](d)=d and numtheory[mobius](n)=1; end; a := []; for n from 1 to 7000 do if test(n) then a := [op(a),n]; end; od; a; %t A075799 Select[Range[10000], PalindromeQ[#] && MoebiusMu[#] == 1 &] (* _Paolo Xausa_, Mar 10 2025 *) %Y A075799 Cf. A046392, A002385, A069217, A032350, A030229, A075800, A075805 (first differences). %K A075799 nonn,base %O A075799 1,2 %A A075799 _Jani Melik_, Oct 13 2002 %E A075799 Edited by _Dean Hickerson_, Oct 21 2002