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 A108660 #6 Mar 03 2014 14:41:29 %S A108660 2,13,31,79,97,227,881,1013,2797,3181,3631,8101,22727,81001,101363, %T A108660 109013,131363,181813,272227,310181,310901,318181,318881,631013, %U A108660 636313,810401,818101,901097,904097,972227,1018813,1090013,1810013,2272727 %N A108660 Square-loop primes. %C A108660 Primes such that each pair of adjacent digits (and also the first and the last ones) sums up to a square. First term is arguable since there is 'no pair of adjacent digits', but there are the "first" and "last" digits. %H A108660 Harvey P. Dale, <a href="/A108660/b108660.txt">Table of n, a(n) for n = 1..120</a> %t A108660 Select[Prime[Range[200000]],And@@(IntegerQ[Sqrt[#]]&/@(Total/@Partition[ IntegerDigits[#],2,1,1]))&] (* _Harvey P. Dale_, Mar 03 2014 *) %Y A108660 Cf. A046704, A007953, A088133, A088134, A088135, A088136, A108659. %K A108660 nonn,base %O A108660 1,1 %A A108660 _Zak Seidov_, Jun 16 2005