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 A088068 #10 May 19 2019 20:37:19 %S A088068 49,1681,1849,3249,6724,8649,9801,11449,13689,13924,20449,24649,28224, %T A088068 37249,42849,57121,59049,63001,66049,85849,94249,106929,110224,117649, %U A088068 127449,135424,154449,165649,190969,196249,208849,243049,257049,265225 %N A088068 Squares sandwiched between two numbers divisible by squares. %C A088068 Sequence is infinite. k^2 is a member if k == 7 (mod 50), or k == -7 (mod 50). %e A088068 49 is a term as 48 and 50 are divisible by squares. %t A088068 okQ[n_]:=Max[Transpose[FactorInteger[n]][[2]]]>1; Select[Range[600]^2,okQ[#-1]&&okQ[#+1]&] (* _Harvey P. Dale_, Jan 26 2011 *) %Y A088068 Cf. A088069. %K A088068 nonn %O A088068 1,1 %A A088068 _Amarnath Murthy_, Sep 22 2003 %E A088068 Corrected and extended by _Ray Chandler_, Sep 27 2003