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 A077684 #28 Jun 05 2025 22:02:16 %S A077684 82,83,85,86,87,89,802,803,805,806,807,809,811,813,814,815,817,818, %T A077684 821,822,823,826,827,829,830,831,834,835,838,839,842,843,849,851,853, %U A077684 854,857,858,859,861,862,863,865,866,869,870,871,874,877,878,879,881,883 %N A077684 Squarefree numbers beginning with 8. %C A077684 Intersection of A005117 and A217401. - _Michel Marcus_, Sep 14 2013 %C A077684 Lower density is 3/(40*Pi^2), upper density is 20/(27*Pi^2). - _Charles R Greathouse IV_, Nov 05 2017 %H A077684 Amiram Eldar, <a href="/A077684/b077684.txt">Table of n, a(n) for n = 1..10000</a> %t A077684 Select[Range[900],SquareFreeQ[#]&&First[IntegerDigits[#]]==8&] (* _Harvey P. Dale_, Feb 22 2011 *) %o A077684 (PARI) is(n)=n>81 && digits(n)[1]==8 && issquarefree(n) \\ _Charles R Greathouse IV_, Nov 05 2017 %Y A077684 Cf. A077677, A077678, A077679, A077680, A077681, A077682, A077683, A077685. %K A077684 base,easy,nonn %O A077684 1,1 %A A077684 _Amarnath Murthy_, Nov 16 2002 %E A077684 More terms from _Sascha Kurz_, Jan 28 2003 %E A077684 Definition clarified by _Harvey P. Dale_, Feb 22 2011