A108660 - OEIS

%I #6 Mar 03 2014 14:41:29

%S 2,13,31,79,97,227,881,1013,2797,3181,3631,8101,22727,81001,101363,

%T 109013,131363,181813,272227,310181,310901,318181,318881,631013,

%U 636313,810401,818101,901097,904097,972227,1018813,1090013,1810013,2272727

%N Square-loop primes.

%C 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 Harvey P. Dale, <a href="/A108660/b108660.txt">Table of n, a(n) for n = 1..120</a>

%t Select[Prime[Range[200000]],And@@(IntegerQ[Sqrt[#]]&/@(Total/@Partition[ IntegerDigits[#],2,1,1]))&] (* _Harvey P. Dale_, Mar 03 2014 *)

%Y Cf. A046704, A007953, A088133, A088134, A088135, A088136, A108659.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Jun 16 2005