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 A065808 #15 Mar 18 2025 11:01:54 %S A065808 7,8,9,10,11,12,13,15,17,18,19,20,21,22,23,25,27,28,29,30,31,32,33,35, %T A065808 37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59, %U A065808 60,61,62,63,65,67,68,69,70,71,72,73,75,77,78,79,80,81,82,83,85,87,88 %N A065808 Square of n has a smaller square as its final digits. %C A065808 Includes all n >= 7 not == 4 or 6 (mod 10). - _Robert Israel_, Oct 24 2017 %H A065808 Robert Israel, <a href="/A065808/b065808.txt">Table of n, a(n) for n = 1..10000</a> %p A065808 filter:= n -> %p A065808 ormap(t -> issqr(n^2 mod 10^t), [$1..ilog10(n^2)]): %p A065808 select(filter, [$1..100]); # _Robert Israel_, Oct 24 2017 %t A065808 ds[n_] := NestWhileList[FromDigits[Rest[IntegerDigits[#]]] &, n, # > 9 &]; Select[Range[4, 88], Or @@ IntegerQ /@ Sqrt[Rest[ds[#^2]]] &] (* _Jayanta Basu_, Jul 10 2013 *) %o A065808 (PARI) %o A065808 a065808(m) = local(k, a, b, d, j, n, r); for(k=1, m, a=length(Str(n))-1; b=1; j=1; n=k^2; while(b, d=divrem(n, 10^j); if(d[1]>0&&issquare(d[2]), b=0; issquare(n, &r); print1(r, ","), if(j<a, j++, b=0)))) %o A065808 a065808(100) %Y A065808 A065807 gives the corresponding squares. %Y A065808 Cf. A065690, A050635, A050637, A050639, A065777, A065780, A065783, A065786, A065789, A065792. %K A065808 base,easy,nonn %O A065808 1,1 %A A065808 _Klaus Brockhaus_, Nov 22 2001 %E A065808 Offset changed to 1 by _Robert Israel_, Oct 24 2017