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Primes expressible as concatenation of reversals of two consecutive squares, in order of their occurrence (ignoring leading zeros).
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%I #27 Jun 21 2020 11:23:10

%S 181,121441,961691,676927,1489,94816391,63139423,631273,63885209,

%T 52096129,10891,4040190601,6992152231,4293116141,16141441,44114641,

%U 96116171,9231348613,4861314023,4213398433,5224369543,12753163,9821742817,14877487,16912769,1276944379,923401679401

%N Primes expressible as concatenation of reversals of two consecutive squares, in order of their occurrence (ignoring leading zeros).

%H K. D. Bajpai, <a href="/A228134/b228134.txt">Table of n, a(n) for n = 1..1000</a>

%e a(3)= 961691. It is a prime and is concatenation of 961 and 691 which are the reversals of 13^2 and 14^2, two consecutive squares.

%p with(StringTools):KD:= proc() local a,b,c,d;a:= parse(Reverse(convert(((n)^2),string))); b:=parse(Reverse(convert(((n+1)^2),string))); d:=parse(cat(a,b)) ;if isprime(d) then RETURN (d) : fi;end:seq(KD(),n=1..500);

%t Select[FromDigits[Flatten[IntegerDigits/@#]]&/@Partition[IntegerReverse/@ (Range[ 400]^2),2,1],PrimeQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 21 2020 *)

%K nonn,base,less

%O 1,1

%A _K. D. Bajpai_, Aug 12 2013