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 A075804 #9 Dec 28 2024 11:52:30 %S A075804 4,1,35,44,11,22,50,41,20,10,10,20,20,41,10,20,41,10,10,20,20,20,41, %T A075804 50,10,31,20,20,10,10,10,10,51,61,20,20,20,20,21,90,332,550,231,220, %U A075804 220,110,110,220,671,110,220,11,110,110,220,110,110,220,341,220,330,341 %N A075804 Differences between adjacent palindromic nonsquarefree numbers A035132. %e A075804 a(1) = 8 - 4 = 4, a(2) = 9 - 8 = 1, a(3) = 44 - 9 = 35. %p A075804 test := proc(n) local d; d := convert(n,base,10); return ListTools[Reverse](d)=d and numtheory[mobius](n)=0; end; s := []; for n from 1 to 7000 do if test(n) then s := [op(s),n]; end; od; a := [op(2..-1,s)-op(1..-2,s)]; %t A075804 Differences[Select[Range[10000],PalindromeQ[#]&&!SquareFreeQ[#]&]] (* _Harvey P. Dale_, Dec 28 2024 *) %Y A075804 Cf. A037010, A035132. %K A075804 nonn,base %O A075804 1,1 %A A075804 _Jani Melik_, Oct 13 2002 %E A075804 Edited by _Dean Hickerson_, Oct 21 2002